diff --git a/.gitignore b/.gitignore
index c3179e3..7aa78e2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,4 +14,5 @@ pyhindsight/static/web_modules/
 .claude/
 hindsight-temp/
 data-sets/
-/temp_outputs/
\ No newline at end of file
+/temp_outputs/
+/test-fixtures/
diff --git a/pyhindsight/lib/components/download/database/proto/download_entry.proto b/pyhindsight/lib/components/download/database/proto/download_entry.proto
new file mode 100644
index 0000000..aa0c1b0
--- /dev/null
+++ b/pyhindsight/lib/components/download/database/proto/download_entry.proto
@@ -0,0 +1,110 @@
+// Copyright 2017 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package download_pb;
+
+import "components/download/database/proto/download_source.proto";
+
+message HttpRequestHeader {
+  optional string key = 1;
+  optional string value = 2;
+}
+
+// Slice information for parallel downloading.
+message ReceivedSlice {
+  optional int64 offset = 1;
+  optional int64 received_bytes = 2;
+  optional bool finished = 3;
+}
+
+// Stores various in-progress metadata related to a download.
+message DownloadEntry {
+  optional string guid = 1;
+  optional string request_origin = 2;
+  optional DownloadSource download_source = 3;
+  optional int64 ukm_download_id = 4;
+  optional int64 bytes_wasted = 5;
+  optional bool fetch_error_body = 6;
+  repeated HttpRequestHeader request_headers = 7;
+}
+
+// Contains a list of entries.
+message DownloadEntries {
+  repeated DownloadEntry entries = 1;
+}
+
+// Information for ukm reporting
+message UkmInfo {
+  optional DownloadSource download_source = 1;
+  optional int64 ukm_download_id = 2;
+}
+
+// Information about when to start the download, used by download later feature.
+// Deprecated.
+message DownloadSchedule {
+  optional int64 start_time = 1;
+}
+
+// Information about an in progress download.
+message InProgressInfo {
+  repeated string url_chain = 1;
+  optional string referrer_url = 2;
+  optional string site_url = 3;  // deprecated
+  optional string tab_url = 4;
+  optional string tab_referrer_url = 5;
+  optional bool fetch_error_body = 6;
+  repeated HttpRequestHeader request_headers = 7;
+  optional string etag = 8;
+  optional string last_modified = 9;
+  optional int64 total_bytes = 10;
+  optional string mime_type = 11;
+  optional string original_mime_type = 12;
+  optional bytes current_path = 13;  // Serialized pickles to support string16
+  optional bytes target_path = 14;   // Serialized pickles to support string16
+  optional int64 received_bytes = 15;
+  optional int64 start_time = 16;
+  optional int64 end_time = 17;
+  repeated ReceivedSlice received_slices = 18;
+  optional bytes hash = 19;  // Hindsight: upstream declares this `string` but it holds the
+                             // raw binary SHA-256; `bytes` lets us extract/hex it cleanly.
+  optional bool transient = 20;
+  optional int32 state = 21;
+  optional int32 danger_type = 22;
+  optional int32 interrupt_reason = 23;
+  optional bool paused = 24;
+  optional bool metered = 25;
+  optional int64 bytes_wasted = 26;
+  optional int32 auto_resume_count = 27;
+  optional DownloadSchedule download_schedule = 28;  // // Deprecated.
+  // Removing DownloadItemRerouteInfo since FileSystem Connector will not
+  // be released, implementation deleted.
+  reserved 29;
+  optional int32 credentials_mode = 30;  // network::mojom::CredentialsMode
+  optional int64 range_request_from = 31;
+  optional int64 range_request_to = 32;
+  optional bytes serialized_embedder_download_data = 33;  // Hindsight: upstream `string`,
+                             // but holds a serialized content.proto.EmbedderDownloadData;
+                             // `bytes` lets us FromString it cleanly.
+  reserved 34;
+  optional bool fetched_via_service_worker = 35;
+}
+
+// Stores various metadata related to a download.
+// WIP and will replace DownloadEntry.
+message DownloadInfo {
+  optional string guid = 1;
+  optional int32 id = 2;
+  optional UkmInfo ukm_info = 3;
+  optional InProgressInfo in_progress_info = 4;
+}
+
+// In progress database entry for download information.
+message DownloadDBEntry {
+  // Add field for offline page download.
+  oneof entry { DownloadInfo download_info = 1; }
+}
diff --git a/pyhindsight/lib/components/download/database/proto/download_source.proto b/pyhindsight/lib/components/download/database/proto/download_source.proto
new file mode 100644
index 0000000..43a8f1c
--- /dev/null
+++ b/pyhindsight/lib/components/download/database/proto/download_source.proto
@@ -0,0 +1,27 @@
+// Copyright 2017 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package download_pb;
+
+// This should stay in sync with the download::DownloadSource enum in
+// components/download/public/common/download_source.h.
+enum DownloadSource {
+  UNKNOWN = 0;
+  NAVIGATION = 1;
+  DRAG_AND_DROP = 2;
+  FROM_RENDERER = 3;
+  EXTENSION_API = 4;
+  EXTENSION_INSTALLER = 5;
+  INTERNAL_API = 6;
+  WEB_CONTENTS_API = 7;
+  OFFLINE_PAGE = 8;
+  CONTEXT_MENU = 9;
+  RETRY = 10;
+  RETRY_FROM_BUBBLE = 11;
+  TOOLBAR_MENU = 12;
+}
diff --git a/pyhindsight/lib/components/performance_manager/persistence/site_data/site_data.proto b/pyhindsight/lib/components/performance_manager/persistence/site_data/site_data.proto
new file mode 100644
index 0000000..0c4e604
--- /dev/null
+++ b/pyhindsight/lib/components/performance_manager/persistence/site_data/site_data.proto
@@ -0,0 +1,49 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+// Contains the information that we want to track about a given site feature.
+// Next Id: 3
+message SiteDataFeatureProto {
+  // The cumulative observation time for this feature in seconds, set to 0 once
+  // this feature has been observed.
+  optional int64 observation_duration = 1;
+  // The time at which this feature has been used (set to 0 if it hasn't been
+  // used), in seconds since epoch.
+  optional int64 use_timestamp = 2;
+}
+
+// Contains decaying average performance measurement estimates.
+// Next Id: 4
+message SiteDataPerformanceMeasurement {
+  // A decaying average of the CPU usage measurements. Units: microseconds.
+  optional float avg_cpu_usage_us = 1;
+  // A decaying average of the process footprint measurements. Units: kilobytes.
+  optional float avg_footprint_kb = 2;
+  // A decaying average of the duration from navigation commit to "loaded".
+  // Units: microseconds.
+  optional float avg_load_duration_us = 3;
+};
+
+// Defines the data that we want to track about a given site.
+// Next Id: 7
+message SiteDataProto {
+  // The last time this site has been in the loaded state, in seconds since
+  // epoch.
+  optional uint32 last_loaded = 1;
+
+  // List of features that we're tracking.
+  optional SiteDataFeatureProto updates_favicon_in_background = 2;
+  optional SiteDataFeatureProto updates_title_in_background = 3;
+  optional SiteDataFeatureProto uses_audio_in_background = 4;
+  optional SiteDataFeatureProto deprecated_uses_notifications_in_background = 5;
+
+  // Load time performance measurement estimates. This maintains a decaying
+  // average of the resource usage of a page until shortly after it becomes
+  // idle.
+  optional SiteDataPerformanceMeasurement load_time_estimates = 6;
+}
\ No newline at end of file
diff --git a/pyhindsight/lib/components/services/storage/service_worker/service_worker_database.proto b/pyhindsight/lib/components/services/storage/service_worker/service_worker_database.proto
new file mode 100644
index 0000000..42499c8
--- /dev/null
+++ b/pyhindsight/lib/components/services/storage/service_worker/service_worker_database.proto
@@ -0,0 +1,304 @@
+// Copyright 2014 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package storage;
+
+message ServiceWorkerOriginTrialFeature {
+  required string name = 1;
+  repeated string tokens = 2;
+}
+
+message ServiceWorkerOriginTrialInfo {
+  repeated ServiceWorkerOriginTrialFeature features = 1;
+}
+
+message ServiceWorkerNavigationPreloadState {
+  required bool enabled = 1;
+  optional string header = 2;
+}
+
+// NEXT ID TO USE: 27
+message ServiceWorkerRegistrationData {
+  enum ServiceWorkerScriptType {
+    CLASSIC = 0;
+    MODULE = 1;
+  }
+  enum ServiceWorkerUpdateViaCacheType {
+    IMPORTS = 0;
+    ALL = 1;
+    NONE = 2;
+  }
+  enum CrossOriginEmbedderPolicyValue {
+    NONE_OR_NOT_EXISTENT = 0;
+    REQUIRE_CORP = 1;
+    CREDENTIALLESS = 2;
+  }
+  enum AncestorFrameType {
+    NORMAL_FRAME = 0;
+    FENCED_FRAME = 1;
+  }
+  enum FetchHandlerSkippableType {
+    reserved 0;  // Deprecated UNKNOWN_FETCH_HANDLER.
+    NOT_SKIPPABLE = 1;
+    SKIPPABLE_EMPTY_FETCH_HANDLER = 2;
+  }
+  enum ReferrerPolicyValue {
+    ALWAYS = 0;
+    DEFAULT = 1;
+    NO_REFERRER_WHEN_DOWNGRADE = 2;
+    NEVER = 3;
+    ORIGIN = 4;
+    ORIGIN_WHEN_CROSS_ORIGIN = 5;
+    STRICT_ORIGIN_WHEN_CROSS_ORIGIN = 6;
+    SAME_ORIGIN = 7;
+    STRICT_ORIGIN = 8;
+  }
+
+  // https://wicg.github.io/local-network-access/
+  enum IPAddressSpace {
+    UNKNOWN = 0;
+    LOOPBACK = 1;
+    LOCAL = 2;
+    PUBLIC = 3;
+  }
+
+  message PolicyContainerPolicies {
+    optional ReferrerPolicyValue referrer_policy = 1 [default = DEFAULT];
+    optional int32 sandbox_flags = 2 [default = 0];
+    optional IPAddressSpace ip_address_space = 3 [default = UNKNOWN];
+    // TODO(crbug.com/4016869): add content security policies
+  }
+
+  message RouterRules {
+    message RuleV1 {
+      message Condition {
+        // Structure representing a URLPattern as described in:
+        // https://wicg.github.io/urlpattern/.
+        message URLPattern {
+          message Part {
+            enum Modifier {
+              kNone = 0;
+              kOptional = 1;
+              kZeroOrMore = 2;
+              kOneOrMore = 3;
+            }
+            // Represents a fixed string part of a URLPattern as described in:
+            // https://wicg.github.io/urlpattern/#part-type-fixed-text
+            message FixedPattern {
+              optional string value = 1;
+            }
+            // Represents either a segment wildcard part or a full wildcard
+            // part of a URLPattern as described in:
+            // https://wicg.github.io/urlpattern/#parts
+            message WildcardPattern {
+              optional string name = 1;
+              optional string prefix = 2;
+              optional string value = 3;
+              optional string suffix = 4;
+            }
+            optional Modifier modifier = 1;
+            oneof pattern {
+              FixedPattern fixed = 2;
+              // Note that kRegex PartType is not implemented because we do not
+              // execute regexp in the browser process for security concerns.
+              // (but reserve 3 for regex just in case).
+              WildcardPattern segment_wildcard = 4;
+              WildcardPattern full_wildcard = 5;
+            }
+          }
+          message Options {
+            optional bool ignore_case = 1 [default = false];
+          }
+
+          repeated Part legacy_pathname = 1;
+
+          repeated Part protocol = 3;
+          repeated Part username = 4;
+          repeated Part password = 5;
+          repeated Part hostname = 2;
+          repeated Part port = 6;
+          repeated Part pathname = 7;
+          repeated Part search = 8;
+          repeated Part hash = 9;
+
+          optional Options options = 10;
+        }
+        message Request {
+          optional string method = 1;
+          // RequestMode in services/network/public/mojom/fetch_api.mojom
+          enum Mode {
+            kSameOriginMode = 0;
+            kNoCorsMode = 1;
+            kCorsMode = 2;
+            kCorsWithForcedPreflightMode = 3;
+            kNavigateMode = 4;
+          }
+          optional Mode mode = 2;
+          // RequestDestination in services/network/public/mojom/fetch_api.mojom
+          enum Destination {
+            kEmptyDestination = 0;
+            kAudioDestination = 1;
+            kAudioWorkletDestination = 2;
+            kDocumentDestination = 3;
+            kEmbedDestination = 4;
+            kFontDestination = 5;
+            kFrameDestination = 6;
+            kIframeDestination = 7;
+            kImageDestination = 8;
+            kManifestDestination = 9;
+            kObjectDestination = 10;
+            kPaintWorkletDestination = 11;
+            kReportDestination = 12;
+            kScriptDestination = 13;
+            kServiceWorkerDestination = 14;
+            kSharedWorkerDestination = 15;
+            kStyleDestination = 16;
+            kTrackDestination = 17;
+            kVideoDestination = 18;
+            kWebBundleDestination = 19;
+            kWorkerDestination = 20;
+            kXsltDestination = 21;
+            kFencedframeDestination = 22;
+            kWebIdentityDestination = 23;
+            kDictionaryDestination = 24;
+            kSpeculationRulesDestination = 25;
+            kJsonDestination = 26;
+            kSharedStorageWorkletDestination = 27;
+            kEmailVerificationDestination = 28;
+          }
+          optional Destination destination = 3;
+        }
+        message RunningStatus {
+          enum Status {
+            kRunning = 0;
+            kNotRunning = 1;
+          }
+          optional Status status = 1;
+        }
+        // TODO(crbug.com/4028565): Remove and replace this to `condition`
+        message ConditionObject {
+          repeated Condition conditions = 1;
+        }
+        message OrCondition {
+          repeated ConditionObject objects = 1;
+        }
+        message NotCondition {
+          required ConditionObject object = 1;
+        }
+        // TODO(crbug.com/4028565): Make this a `message` to fit WebIDL
+        oneof condition {
+          // Used for representing URLPattern.
+          URLPattern url_pattern = 1;
+          // Used for representing Request.
+          Request request = 2;
+          // Used for representing running status.
+          RunningStatus running_status = 3;
+          // Used for representing 'or' condition.
+          // The `_condition` suffix is to avoid conflicts with keywords in C++
+          OrCondition or_condition = 4;
+          // Used for representing 'not' condition.
+          // The `_condition` suffix is to avoid conflicts with keywords in C++
+          NotCondition not_condition = 5;
+        }
+      }
+      message Source {
+        message NetworkSource {}
+        message RaceNetworkAndFetchEventSource {
+          reserved 1;        // Deprecated
+          reserved "target"; // Deprecated
+        }
+        message FetchEventSource {}
+        message CacheSource {
+          optional string cache_name = 1;
+        }
+        message RaceNetworkAndCacheSource {
+          required CacheSource cache_source = 1;
+        }
+        oneof source {
+          NetworkSource network_source = 1;
+          RaceNetworkAndFetchEventSource race_network_and_fetch_event_source =
+              2;
+          FetchEventSource fetch_event_source = 3;
+          CacheSource cache_source = 4;
+          RaceNetworkAndCacheSource race_network_and_cache_source = 5;
+        }
+      }
+      repeated Condition condition = 1;
+      repeated Source source = 2;
+    }
+
+    required int32 version = 1;
+    repeated RuleV1 v1 = 2;
+  }
+
+  required int64 registration_id = 1;
+  required string scope_url = 2;
+  required string script_url = 3;
+
+  // Versions are first stored once they successfully install and become the
+  // waiting version. Then they are updated when they transition to the active
+  // version.
+  required int64 version_id = 4;
+
+  required bool is_active = 5;
+  required bool has_fetch_handler = 6;
+  optional FetchHandlerSkippableType fetch_handler_skippable_type = 22;
+
+  // Serialized by Time::FromDeltaSinceWindowsEpoch().
+  required int64 last_update_check_time = 7;
+
+  optional uint64 resources_total_size_bytes = 8;
+
+  // repeated string foreign_fetch_scope = 9;  // obsolete
+  // repeated string foreign_fetch_origin = 10; // obsolete
+
+  // If the registration data was created by old Chrome (< M56),
+  // |origin_trial_tokens| is not set. In this case, we have to start the
+  // Service Worker and load the main script resource in ServiceWorkerStorage
+  // to check the HTTP header.
+  optional ServiceWorkerOriginTrialInfo origin_trial_tokens = 11;
+
+  optional ServiceWorkerNavigationPreloadState navigation_preload_state = 12;
+
+  // The set of features that the worker used up until the time installation
+  // completed. The values must be from blink::UseCounter::Feature enum.
+  repeated uint32 used_features = 13;
+
+  optional ServiceWorkerUpdateViaCacheType update_via_cache = 14
+      [default = IMPORTS];
+  optional ServiceWorkerScriptType script_type = 15 [default = CLASSIC];
+
+  // The time when the browser received the service worker main script,
+  // serialized by Time::ToDeltaSinceWindowsEpoch().
+  optional int64 script_response_time = 16;
+
+  optional CrossOriginEmbedderPolicyValue cross_origin_embedder_policy_value =
+      17 [default = NONE_OR_NOT_EXISTENT];
+  optional string cross_origin_embedder_policy_reporting_endpoint = 18;
+  optional CrossOriginEmbedderPolicyValue
+      cross_origin_embedder_policy_report_only_value = 19
+      [default = NONE_OR_NOT_EXISTENT];
+  optional string cross_origin_embedder_policy_report_only_reporting_endpoint =
+      20;
+  optional AncestorFrameType ancestor_frame_type = 21 [default = NORMAL_FRAME];
+
+  optional PolicyContainerPolicies policy_container_policies = 23;
+
+  optional RouterRules router_rules = 24;
+
+  optional bool has_hid_event_handlers = 25;
+
+  optional bool has_usb_event_handlers = 26;
+}
+
+message ServiceWorkerResourceRecord {
+  required int64 resource_id = 1;
+  required string url = 2;
+  optional uint64 size_bytes = 3;
+  optional string sha256_checksum = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/BUILD.gn b/pyhindsight/lib/components/sync/protocol/BUILD.gn
new file mode 100644
index 0000000..50219ae
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/BUILD.gn
@@ -0,0 +1,83 @@
+# Copyright 2014 The Chromium Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/protobuf/proto_library.gni")
+import("protocol_sources.gni")
+
+proto_library("protocol") {
+  proto_in_dir = "//"
+  sources = sync_protocol_sources
+  extra_configs = [ "//build/config/compiler:wexit_time_destructors" ]
+}
+
+# TODO(crbug.com/41449994): It seems some code implicitly depends on "util" due to
+# it being listed in public_deps of upper directories (even though it doesn't
+# fit the definition of public_deps). Consider using a group() to expose this
+# together with the "protocol" target and simplify things.
+static_library("util") {
+  sources = [
+    "collaboration_metadata.cc",
+    "collaboration_metadata.h",
+    "data_type_state_helper.cc",
+    "data_type_state_helper.h",
+    "entity_data.cc",
+    "entity_data.h",
+    "proto_enum_conversions.cc",
+    "proto_enum_conversions.h",
+    "proto_memory_estimations.cc",
+    "proto_memory_estimations.h",
+    "proto_value_conversions.cc",
+    "proto_value_conversions.h",
+    "proto_visitors.h",
+  ]
+
+  public_deps = [
+    "//base",
+    "//components/sync/base",
+    "//google_apis",
+  ]
+}
+
+if (is_android) {
+  import("//build/config/android/rules.gni")
+
+  proto_java_library("protocol_java") {
+    proto_path = "//"
+    sources = sync_protocol_sources
+  }
+}
+
+action("prepare_full_proto") {
+  script = "prepare_full_proto.py"
+
+  inputs = [
+    "sync_collaboration_attribution.proto",
+    "shared_tab_group_data_specifics.proto",
+    "unique_position.proto",
+  ]
+
+  outputs = [
+    "$target_gen_dir/sync_collaboration_attribution_full_proto.proto",
+    "$target_gen_dir/shared_tab_group_data_specifics_full_proto.proto",
+    "$target_gen_dir/unique_position_full_proto.proto",
+  ]
+
+  args = [ rebase_path(target_gen_dir, root_build_dir) ]
+
+  foreach(f, inputs) {
+    args += [ rebase_path(f, root_build_dir) ]
+  }
+}
+
+proto_library("full_proto") {
+  testonly = true
+  proto_in_dir = root_gen_dir
+  proto_out_dir = "."
+  sources = get_target_outputs(":prepare_full_proto")
+
+  proto_deps = [ ":prepare_full_proto" ]
+
+  use_protobuf_full = true
+  import_dirs = [ "//third_party/protobuf/src" ]
+}
diff --git a/pyhindsight/lib/components/sync/protocol/DEPS b/pyhindsight/lib/components/sync/protocol/DEPS
new file mode 100644
index 0000000..eae6436
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/DEPS
@@ -0,0 +1,4 @@
+include_rules = [
+  "+components/sync/base",
+  "+google/protobuf/descriptor.h"  # for unit tests.
+]
diff --git a/pyhindsight/lib/components/sync/protocol/README.md b/pyhindsight/lib/components/sync/protocol/README.md
new file mode 100644
index 0000000..0425ed5
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/README.md
@@ -0,0 +1,33 @@
+Sync Protocol Style
+===================
+
+General guidelines:
+* Follow the [Protocol Buffers Style Guide](https://developers.google.com/protocol-buffers/docs/style)
+* Follow the [Proto Do's and Don'ts](http://go/protodosdonts) (sorry, Googlers only).
+* Maintain local consistency.
+* Use proto2 syntax.
+
+Some specific guidelines on top of the general ones above, or just things that often come up:
+* Avoid using "explicit version numbers" in your protobuf; instead, have your code test for the existence of a field to determine what to do. Protobufs were written precisely to avoid version-specific logic, and testing for fields is more robust.
+* Enum entries should be in ALL_CAPS (different from C++!), and for new code, the first entry should be a `FOO_UNSPECIFIED = 0` one.
+* Timestamp fields must specify their epoch and unit in a suffix, in this format: `_[unix|windows]_epoch_[seconds|millis|micros|nanos]`, e.g `creation_time_unix_epoch_millis`.
+  * Many existing fields do not follow this format, and specify epoch/unit in a comment instead. Follow the format for all new fields, though!
+* Similarly, duration fields must specify their unit as `_[minutes|seconds|millis|...]`.
+* Proto changes also require corresponding changes in [proto_visitors.h](https://source.chromium.org/chromium/chromium/src/+/main:components/sync/protocol/proto_visitors.h) and (where appropriate) in [proto_enum_conversions.h/cc](https://source.chromium.org/chromium/chromium/src/+/main:components/sync/protocol/proto_enum_conversions.cc).
+* Backwards compatibility: In general, all changes must be fully backwards-compatible - consider that a single user might be running different versions of the browser simultaneously! Also note that Sync supports clients up to a few years old, so deprecating/removing an existing field is typically a multi-year process.
+  * As one special case, **renaming** a field **within a specifics message** is generally safe (unless there are special server-side integrations that depend on the name). However, **never** rename fields anywhere outside of specifics.
+  * Avoid repurposing existing fields. Instead, add a new field for the new data and deprecate the old field. Also consider adding code to migrate the old field to the new field.
+* Adding fields:
+  * Any new fields in a proto are unrecognized by older clients. Thus, any such change faces an inherent risk of leading to data loss for a multi-client Sync user when an older client commits. It is recommended for the data type to follow [Protection against data override by old Sync clients][forward-compatibility] for forward-compatibility.
+* Deprecating fields:
+  * If the field **is** still accessed: Mark it as `[deprecated = true]`. This is the common case, since the browser typically needs to continue supporting the old field for backwards compatibility reasons.
+  * If the field **is not** accessed anymore (i.e. no non-ancient clients depend on the field being populated anymore, all migration code has been retired, etc): Remove the field, and add `reserved` entries for both its name and its tag number.
+  * **Note**: If your data type is using the [Protection against data override by old Sync clients][forward-compatibility], then even fields that aren't accessed anymore should **not** be removed from the proto definition, since they should still be treated as supported for the purpose of trimming. (Otherwise, the removed fields would forever be carried forward in the data.)
+
+* Deprecating enum values: This is particularly tricky, especially if the default value is not a `FOO_UNSPECIFIED` one (see above). A common pattern is prepending `DEPRECATED_` to the entry name.
+
+For reviewers:
+* Be extra careful with protocol changes, especially consider backward and forward compatibility.
+* In doubt, loop in a second reviewer from the Sync team.
+
+[forward-compatibility]: https://www.chromium.org/developers/design-documents/sync/old-sync-clients-data-override-protection/
diff --git a/pyhindsight/lib/components/sync/protocol/app_list_specifics.proto b/pyhindsight/lib/components/sync/protocol/app_list_specifics.proto
new file mode 100644
index 0000000..375b99c
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/app_list_specifics.proto
@@ -0,0 +1,90 @@
+// Copyright 2013 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for the app list (aka app launcher).
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of app list objects.
+message AppListSpecifics {
+  // Unique identifier for the item:
+  // * TYPE_FOLDER: Folder id (generated)
+  // * TYPE_APP: App Id
+  optional string item_id = 1;
+
+  // What type of item this is.
+  enum AppListItemType {
+    // An app, whether a web app, Android app, etc.
+    //
+    // For bookmark apps (URL shortcuts), additional information such as their
+    // URLs are kept in the AppSpecifics.bookmark_app_foobar fields.
+    TYPE_APP = 1;
+    // A request to remove any matching default installed apps.
+    TYPE_REMOVE_DEFAULT_APP = 2;
+    // A folder containing entries whose `parent_id` matches `item_id`.
+    TYPE_FOLDER = 3;
+    // Obsolete type, intended for URL shortcuts, that was never implemented.
+    TYPE_OBSOLETE_URL = 4;
+    // A "page break" item (Indicate creation of a new page in app list).
+    TYPE_PAGE_BREAK = 5;
+  }
+  optional AppListItemType item_type = 2;
+
+  // Item name (FOLDER).
+  optional string item_name = 3;
+
+  // Id of the parent (folder) item.
+  optional string parent_id = 4;
+
+  // Marked OBSOLETE because this is unused for the app list.
+  // Which page this item will appear on in the app list.
+  optional string OBSOLETE_page_ordinal = 5 [deprecated = true];
+
+  // Where on a page this item will appear.
+  optional string item_ordinal = 6;
+
+  // Where on a shelf this item will appear.
+  optional string item_pin_ordinal = 7;
+
+  // The color groups used for grouping together icons by colors.
+  enum ColorGroup {
+    COLOR_EMPTY = 0;
+    COLOR_WHITE = 1;
+    COLOR_RED = 2;
+    COLOR_ORANGE = 3;
+    COLOR_YELLOW = 4;
+    COLOR_GREEN = 5;
+    COLOR_BLUE = 6;
+    COLOR_MAGENTA = 7;
+    COLOR_BLACK = 8;
+  }
+
+  message IconColor {
+    // The item icon's background color.
+    optional ColorGroup background_color = 1;
+
+    // The item icon's hue.
+    optional int32 hue = 2;
+  }
+  optional IconColor item_color = 8;
+
+  // This field previously stored the is_user_pinned value, which has been
+  // removed.
+  reserved 9;
+
+  // Identifier for the app package of the item. Package Ids are stable and
+  // globally unique across app platforms, whereas App Id stored in item_id is
+  // not.
+  optional string promise_package_id = 10;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/app_setting_specifics.proto b/pyhindsight/lib/components/sync/protocol/app_setting_specifics.proto
new file mode 100644
index 0000000..8e9d93a
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/app_setting_specifics.proto
@@ -0,0 +1,26 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for an app setting.
+// This is the same as for an extension setting, but uses a separate datatype
+// in order to control syncability separately.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/extension_setting_specifics.proto";
+
+// Properties of app setting sync objects; just an extension setting.
+message AppSettingSpecifics {
+  optional ExtensionSettingSpecifics extension_setting = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/app_specifics.proto b/pyhindsight/lib/components/sync/protocol/app_specifics.proto
new file mode 100644
index 0000000..4ab12d0
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/app_specifics.proto
@@ -0,0 +1,101 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for apps.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/extension_specifics.proto";
+
+// Settings related to push notifications for apps.
+message AppNotificationSettings {
+  // DEPRECATED: Use oauth_client_id below.
+  // Whether or not the user has setup notifications at least once.
+  // The value for this field will start out false and will be set
+  // to true when the user accepts receiving notifications for the
+  // first time and then it will always remain true.
+  optional bool initial_setup_done = 1 [deprecated = true];
+
+  // Whether or not the user has disabled notifications.
+  optional bool disabled = 2;
+
+  // OAuth2 client id to which the user granted the notification permission.
+  // This field will start out empty.
+  // It will be set when the user accepts receiving notifications.
+  // This field is used when the user revokes the notifications permission.
+  // Note that it is never cleared after it was set once. Hence, the presence
+  // of this field can be used to determine if the user has setup notifications
+  // at least once for the given app.
+  optional string oauth_client_id = 3;
+}
+
+// Information about a linked app icon.
+message LinkedAppIconInfo {
+  // The URL of the app icon.
+  optional string url = 1;
+
+  // The size of the app icon in DIPs.
+  optional uint32 size = 2;
+}
+
+// Properties of app sync objects.
+//
+// For now, an app is just an extension.  We keep the two data types
+// separate for future-proofing purposes.
+message AppSpecifics {
+  // Extension data.
+  optional ExtensionSpecifics extension = 1;
+
+  // Notification settings.
+  optional AppNotificationSettings notification_settings = 2;
+
+  // This controls where on a page this application icon will appear.
+  optional string app_launch_ordinal = 3;
+
+  // This specifics which page the application icon will appear on in the NTP.
+  // This values only provide the order within the application pages, not within
+  // all of the panels in the NTP.
+  optional string page_ordinal = 4;
+
+  // The possible launch types for an app.
+  // This enum should be kept in sync with extensions::LaunchType.
+  enum LaunchType {
+    PINNED = 0;
+    REGULAR = 1;
+    FULLSCREEN = 2;
+    WINDOW = 3;
+  }
+
+  // This describes how the extension should be launched.
+  optional LaunchType launch_type = 5;
+
+  // DEPRECATED. See https://crbug.com/1233303.
+  optional string bookmark_app_url = 6 [deprecated = true];
+
+  // DEPRECATED. See https://crbug.com/1233303.
+  optional string bookmark_app_description = 7 [deprecated = true];
+
+  // DEPRECATED. See https://crbug.com/1233303.
+  optional string bookmark_app_icon_color = 8 [deprecated = true];
+
+  // This is information about linked icons (that is, icons that are downloaded
+  // from outside the app's bundle of files.
+  repeated LinkedAppIconInfo linked_app_icons = 9;
+
+  // DEPRECATED. See https://crbug.com/1233303.
+  optional string bookmark_app_scope = 10 [deprecated = true];
+
+  // DEPRECATED. See https://crbug.com/1233303.
+  optional uint32 bookmark_app_theme_color = 11 [deprecated = true];
+}
diff --git a/pyhindsight/lib/components/sync/protocol/arc_package_specifics.proto b/pyhindsight/lib/components/sync/protocol/arc_package_specifics.proto
new file mode 100644
index 0000000..6720158
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/arc_package_specifics.proto
@@ -0,0 +1,30 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for ARC pakcages.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of arc package objects.
+message ArcPackageSpecifics {
+  // Unique identifier for the item:
+  // Android package name.
+  optional string package_name = 1;
+  // Android package version.
+  optional int32 package_version = 2;
+  // Last Android id generated when Android side backups data.
+  optional int64 last_backup_android_id = 3;
+  // Last time internal value that Android side backups data.
+  optional int64 last_backup_time = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/autofill_offer_specifics.proto b/pyhindsight/lib/components/sync/protocol/autofill_offer_specifics.proto
new file mode 100644
index 0000000..c92e98d
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/autofill_offer_specifics.proto
@@ -0,0 +1,108 @@
+// Copyright 2020 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of Autofill wallet offer related objects.
+
+// Next tag: 11
+message AutofillOfferSpecifics {
+  // The id for this offer data. Will be used as the client tag.
+  optional int64 id = 1;
+
+  // The link leading to the offer details page on Gpay app. Will be populated
+  // on Android only.
+  optional string offer_details_url = 2;
+
+  // Merchant domain and merchant app package name refers to the merchant this
+  // offer is applied to.
+  repeated string merchant_domain = 3;
+  repeated string merchant_app_package = 4;
+
+  // The expiry of this offer. Will be represented in the form of unix epoch
+  // time in seconds. Once the offer is expired it will not be shown in the
+  // client.
+  optional int64 offer_expiry_date = 5;
+
+  // Proto containing data specific to a card-linked offer.
+  message CardLinkedOfferData {
+    reserved 1, 2;
+
+    // The server id of the card to which the offer is linked.
+    repeated int64 instrument_id = 3;
+  }
+
+  // Proto containing data specific to a promo code offer.
+  message PromoCodeOfferData {
+    // The actual promo code which can be applied at checkout.
+    optional string promo_code = 1;
+  }
+
+  // The unique offer data for different offer types.
+  oneof type_specific_offer_data {
+    CardLinkedOfferData card_linked_offer_data = 6;
+    PromoCodeOfferData promo_code_offer_data = 9;
+  }
+
+  // Strings to be shown in client UI, based on the offer type and details.
+  message DisplayStrings {
+    // A message translated in the user's GPay app locale, explaining the value
+    // of the offer. For example, a promo code offer might display
+    // "$5 off on shoes, up to $50."
+    optional string value_prop_text = 1;
+
+    // A message translated in the user's GPay app locale and shown on mobile as
+    // a link, prompting the user to click it to learn more about the offer.
+    // Generally, "See details".
+    optional string see_details_text_mobile = 2;
+
+    // A message translated in the user's GPay app locale and shown on desktop
+    // (not as a link), informing the user that exclusions and restrictions may
+    // apply to the value prop text. Generally, "Terms apply."
+    optional string see_details_text_desktop = 3;
+
+    // A message translated in the user's GPay app locale and shown on mobile,
+    // instructing them on how to redeem the offer. For example, a promo code
+    // offer might display "Tap the promo code field at checkout to autofill
+    // it."
+    optional string usage_instructions_text_mobile = 4;
+
+    // A message translated in the user's GPay app locale and shown on desktop,
+    // instructing them on how to redeem the offer. For example, a promo code
+    // offer might display "Click the promo code field at checkout to autofill
+    // it."
+    optional string usage_instructions_text_desktop = 5;
+  }
+  optional DisplayStrings display_strings = 10;
+
+  // This value will be shown in the offer text template as "XXX% cashback".
+  // Percentage has a range of (0, 100].
+  message PercentageReward {
+    // The string contains a number and a percent sign.
+    optional string percentage = 1;
+  }
+
+  // This value will be shown in the offer text template as "XXX$ off".
+  message FixedAmountReward {
+    // The string contains a number and a currency sign.
+    optional string amount = 1;
+  }
+
+  // The reward type of the offer. Will be used to generate the display text in
+  // the UI. Each type has its own client side text template.
+  oneof reward_type {
+    PercentageReward percentage_reward = 7;
+    FixedAmountReward fixed_amount_reward = 8;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/autofill_specifics.proto b/pyhindsight/lib/components/sync/protocol/autofill_specifics.proto
new file mode 100644
index 0000000..2b298f1
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/autofill_specifics.proto
@@ -0,0 +1,839 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for autofill.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of autofill sync objects.
+
+// An AutofillProfile.
+message AutofillProfileSpecifics {
+  // Represents the validation status of value stored in the AutofillProfile.
+  enum VerificationStatus {
+    // No verification status assigned.
+    VERIFICATION_STATUS_UNSPECIFIED = 0;
+    // The value token was parsed from a parent token.
+    // For example, the first name was derived by splitting a full name into
+    // its components.
+    PARSED = 1;
+    // Value was built from its subcomponents.
+    // For example, the full name was built from the first, middle and last
+    // name.
+    FORMATTED = 2;
+    // The value was observed in a form transmission.
+    // For example, the user filled a form that contained at NAME_FULL field.
+    // The value of NAME_FULL will be stored as OBSERVED.
+    OBSERVED = 3;
+    // The user used the autofill settings to verify and store this token.
+    // This is currently only applicable to the full name, since users cannot
+    // edit individual components of their name.
+    USER_VERIFIED = 4;
+    // The token was parsed remotely.
+    SERVER_PARSED = 5;
+  }
+
+  optional string guid = 15;
+  // Starting from M115, Autofill ignores the origin and doesn't distinguish
+  // between verified (meaning `deprecated_origin == kSettingsOrigin`) and
+  // unverified profiles anymore. However, clients prior to this milestone only
+  // accept updates to verified profiles through Sync if the remote profile is
+  // verified as well. For this reason, M115 clients and above always set the
+  // origin to kSettingsOrigin.
+  // TODO(crbug.com/40266694): Remove in a few milestones.
+  optional string deprecated_origin = 16;
+  optional int64 use_count = 22;
+
+  // The time_t value of the last time this profile was used. This
+  // value makes sense wrt base::Time::To/FromTimeT, which measures
+  // from the Windows epoch.
+  optional int64 use_date = 23;
+
+  // A label intended to be chosen by the user. This was however never
+  // implemented and is currently unused.
+  optional string profile_label = 62;
+
+  // Contact info name fields.
+  repeated string name_first = 2;
+  repeated string name_middle = 3;
+  repeated string name_last = 4;
+
+  // A name_last consists of a prefix and a core (e.g., "van" and "Gogh" in
+  // "van Gogh"). Used for more granular name representation of last names
+  // with prefixes.
+  repeated string name_last_prefix = 99;
+  repeated string name_last_core = 100;
+
+  // Sometimes the last name is composed of two names as it is common for
+  // Hispanic/Latinx names. In the unstructured representation of the last name,
+  // there may be even a conjunction between the first and the second last
+  // name. For example, the more-complete version of Pablo Picasso's surname is
+  // "Ruiz y Picasso" containing a first last name, a conjunction (the y) and a
+  // second last name.
+  repeated string name_last_first = 27;
+  repeated string name_last_conjunction = 28;
+  repeated string name_last_second = 29;
+  repeated string name_full = 21;
+
+  reserved 60;
+  reserved "name_full_with_honorific";
+
+  // Contact info alternative name fields (e.g. phonetic names in Japan).
+  optional string alternative_full_name = 93;
+  optional string alternative_given_name = 94;
+  optional string alternative_family_name = 95;
+
+  // Validation status records for name fields.
+  reserved 30;
+  reserved "name_honorific_status";
+  repeated VerificationStatus name_first_status = 31;
+  repeated VerificationStatus name_middle_status = 32;
+  repeated VerificationStatus name_last_status = 33;
+  repeated VerificationStatus name_last_prefix_status = 101;
+  repeated VerificationStatus name_last_core_status = 102;
+  repeated VerificationStatus name_last_first_status = 34;
+  repeated VerificationStatus name_last_conjunction_status = 35;
+  repeated VerificationStatus name_last_second_status = 36;
+  repeated VerificationStatus name_full_status = 37;
+  reserved 61;
+  reserved "name_full_with_honorific_status";
+
+  // Validation status records for alternative name fields.
+  optional VerificationStatus alternative_full_name_status = 96;
+  optional VerificationStatus alternative_given_name_status = 97;
+  optional VerificationStatus alternative_family_name_status = 98;
+
+  // Contact info additional fields.
+  repeated string email_address = 5;
+  optional string company_name = 6;
+
+  // Address field.
+  // The address_home_line1/2 fields are deprecated and
+  // address_home_street_address should be used instead by
+  // joining address_home_line1/2 with a newline ("\n").
+  // Full deprecation can not be achieved before all sync profiles have been
+  // updated with a M86+ client.
+  // TODO(crbug.com/40142711): Remove usages of address_home_line1/2 and mark
+  // field as deprecated.
+  optional string address_home_line1 = 7;
+  optional string address_home_line2 = 8;
+  optional string address_home_city = 9;
+  optional string address_home_state = 10;
+  optional string address_home_zip = 11;
+  optional string address_home_country = 12;
+  optional string address_home_admin_level_2 = 71;
+
+  // Additional address fields for i18n.
+  optional string address_home_street_address = 17;
+  optional string address_home_sorting_code = 18;
+  optional string address_home_dependent_locality = 19;
+  optional string address_home_language_code = 20;
+  optional string address_home_thoroughfare_name = 38;
+  optional string address_home_thoroughfare_number = 39;
+  optional string address_home_street_location = 73;
+  optional string address_home_subpremise_name = 42;
+  // All the information related to the apartment. Normally a combination of the
+  // apartment type (address_home_apt_type) and number (address_home_apt_num).
+  // E.g. "Apt 5".
+  optional string address_home_apt = 85;
+  // The raw number (or identifier) of an apartment (e.g. "5") but without a
+  // prefix. The value "apt 5" would correspond to the address_home_apt.
+  optional string address_home_apt_num = 56;
+  // Information describing the type of apartment (e.g. Apt, Apartamento, Sala,
+  // Departamento).
+  optional string address_home_apt_type = 87;
+  optional string address_home_floor = 57;
+  optional string address_home_landmark = 67;
+  // The type indicates that the address is at the intersection between two
+  // streets. This is a common way of writing addresses in Mexico.
+  optional string address_home_between_streets = 69;
+  // The meaning of the field is similar to address_home_between_streets. The
+  // type should be used for "Entre calle 1" in MX addresses which also
+  // contain the "Entre calle 2" field.
+  optional string address_home_between_streets_1 = 77;
+  // The meaning of the field is similar to address_home_between_streets. The
+  // type should be used for "Entre calle 2" in MX addresses which also
+  // contain the "Entre calle 1" field.
+  optional string address_home_between_streets_2 = 79;
+  optional string address_home_overflow = 75;
+  // Combination of types address_home_between_streets or address_home_landmark.
+  // Note that some address forms require the combination of both in a single
+  // field as opposed to each one separately.
+  optional string address_home_between_streets_or_landmark = 81;
+  // Combination of types address_home_overflow and address_home_landmark.
+  // Note that some address forms require the combination of both in a single
+  // field as opposed to each one separately.
+  optional string address_home_overflow_and_landmark = 83;
+  // Combination of types address_home_street_location and
+  // address_home_dependent_locality. Note that some address forms require the
+  // combination of both in a single field as opposed to each one separately.
+  optional string address_home_street_location_and_locality = 89;
+  // Combination of types address_home_thoroughfare_number and
+  // address_home_apt. Note that some address forms require the combination of
+  // both in a single field as opposed to each one separately.
+  optional string address_home_thoroughfare_number_and_apt = 91;
+  // Sometimes address_home_zip consists of two parts.
+  // For example, address_home_zip = 12345-6789,
+  // prefix = 12345, suffix = 6789.
+  optional string address_home_zip_prefix = 103;
+  optional string address_home_zip_suffix = 104;
+
+  // Validation status records for address fields.
+  optional VerificationStatus address_home_city_status = 43;
+  optional VerificationStatus address_home_state_status = 44;
+  optional VerificationStatus address_home_zip_status = 45;
+  optional VerificationStatus address_home_country_status = 46;
+  optional VerificationStatus address_home_landmark_status = 68;
+  optional VerificationStatus address_home_between_streets_status = 70;
+  optional VerificationStatus address_home_between_streets_1_status = 78;
+  optional VerificationStatus address_home_between_streets_2_status = 80;
+  optional VerificationStatus address_home_admin_level_2_status = 72;
+  optional VerificationStatus address_home_overflow_status = 76;
+  optional VerificationStatus address_home_between_streets_or_landmark_status =
+      82;
+  optional VerificationStatus address_home_overflow_and_landmark_status = 84;
+  optional VerificationStatus address_home_street_location_and_locality_status =
+      90;
+  optional VerificationStatus address_home_thoroughfare_number_and_apt_status =
+      92;
+  optional VerificationStatus address_home_street_address_status = 47;
+  optional VerificationStatus address_home_sorting_code_status = 48;
+  optional VerificationStatus address_home_dependent_locality_status = 49;
+  optional VerificationStatus address_home_language_code_status = 50;
+  optional VerificationStatus address_home_thoroughfare_name_status = 51;
+  optional VerificationStatus address_home_thoroughfare_number_status = 52;
+  optional VerificationStatus address_home_street_location_status = 74;
+  optional VerificationStatus address_home_subpremise_name_status = 55;
+  optional VerificationStatus address_home_apt_status = 86;
+  optional VerificationStatus address_home_apt_num_status = 58;
+  optional VerificationStatus address_home_apt_type_status = 88;
+  optional VerificationStatus address_home_floor_status = 59;
+  optional VerificationStatus address_home_zip_prefix_status = 105;
+  optional VerificationStatus address_home_zip_suffix_status = 106;
+
+  // Phone.
+  repeated string phone_home_whole_number = 13;
+
+  reserved 63;
+  reserved "disallow_settings_visible_updates";
+
+  // Removed in M123.
+  reserved 64;
+  reserved "birthdate_day";
+  reserved 65;
+  reserved "birthdate_month";
+  reserved 66;
+  reserved "birthdate_year";
+
+  // Deprecated.
+  optional string deprecated_label = 1 [deprecated = true];
+  optional string phone_fax_whole_number = 14 [deprecated = true];
+  // The following validity-related fields have only been used in combination
+  // with an experimental features that are disabled for all clients and have
+  // been removed in M100.
+  optional int64 validity_state_bitfield = 24 [deprecated = true];
+  optional bool is_client_validity_states_updated = 25 [deprecated = true];
+  // Removed in M118.
+  reserved 40;
+  reserved "address_home_dependent_thoroughfare_name";
+  reserved 41;
+  reserved "address_home_premise_name";
+  reserved 53;
+  reserved "address_home_dependent_thoroughfare_name_status";
+  reserved 54;
+  reserved "address_home_premise_name_status";
+  // Removed in M122.
+  reserved 26;
+  reserved "name_honorific";
+}
+
+message AutofillSpecifics {
+  // If any of these 3 fields are present, then all 3 should be, and it implies
+  // that this entity represents a classic autofill object.  In this case,
+  // none of the autofill++ objects below should be present.
+  optional string name = 1;
+  optional string value = 2;
+  repeated int64 usage_timestamp = 3;
+
+  // An autofill++ profile object.  If present, indicates this entity
+  // represents an AutofillProfile exclusively, and no other fields (such as
+  // name/value or credit_card) should be present.
+  optional AutofillProfileSpecifics profile = 4;
+
+  reserved 5;
+  reserved "encrypted_credit_card";
+  reserved 6;
+  reserved "credit_card";
+}
+
+// TODO(crbug.com/40105930): Deprecated, remove this once dependent change is
+// done. Use WalletCreditCardCloudTokenData instead.
+message CloudTokenData {
+  // Last 4-5 digits of the Cloud Primary Account Number (CPAN).
+  optional string suffix = 1;
+
+  // CPAN Month number 1-12.
+  optional int32 exp_month = 2;
+
+  // CPAN Four-digit year (e.g. 2017).
+  optional int32 exp_year = 3;
+
+  // URL of the card art to be displayed for CPAN.
+  optional string art_fife_url = 4;
+
+  // Opaque identifier for the cloud token associated with the payment
+  // instrument.
+  optional string instrument_token = 5;
+}
+
+// Next id: 8
+message CardBenefit {
+  // The unique identifier of the benefit. Generated originally in Chrome Sync
+  // server.
+  optional string benefit_id = 7;
+
+  // The benefit description (Engligh only currently) to be shown in the UI.
+  optional string benefit_description = 1;
+
+  // When the benefit should be displayed, in UTC time.
+  optional int64 start_time_unix_epoch_milliseconds = 2;
+  optional int64 end_time_unix_epoch_milliseconds = 3;
+
+  // Proto containing data specific to a flat rate benefit. Empty as flat rate
+  // benefits don't have unique fields. The actual benefit (e.g. "2% cash back")
+  // is already included in the `benefit_description`.
+  message FlatRateBenefit {}
+
+  // For category benefits, represents the category of purchases that the
+  // benefit can be applied to.
+  enum CategoryBenefitType {
+    CATEGORY_BENEFIT_TYPE_UNKNOWN = 0;
+    SUBSCRIPTION = 1;
+    FLIGHTS = 2;
+    DINING = 3;
+    ENTERTAINMENT = 4;
+    STREAMING = 5;
+    GROCERY_STORES = 6;
+    AIR_MILES_PARTNER = 7;
+    ALCOHOL_STORES = 8;
+    DRUGSTORES = 9;
+    OFFICE_SUPPLIES = 10;
+    RECURRING_BILLS = 11;
+    TRANSIT = 12;
+    TRAVEL = 13;
+    WHOLESALE_CLUBS = 14;
+  }
+
+  // Proto containing data specific to a category benefit.
+  message CategoryBenefit {
+    // The type of category purchases the benefit is eligible on.
+    optional CategoryBenefitType category_benefit_type = 1;
+  }
+
+  // Proto containing data specific to a merchant benefit.
+  message MerchantBenefit {
+    // The merchant domain that the benefit is eligible on.
+    // Example: https://www.acme.com
+    repeated string merchant_domain = 1;
+  }
+
+  // Proto data representing the actual data of the credit card benefit,
+  // depending on the benefit type.
+  oneof DomainSpecificBenefit {
+    FlatRateBenefit flat_rate_benefit = 4;
+    CategoryBenefit category_benefit = 5;
+    MerchantBenefit merchant_benefit = 6;
+  }
+}
+
+message CardIssuer {
+  enum Issuer {
+    ISSUER_UNKNOWN = 0;
+    // Card where the issuer is Google.
+    GOOGLE = 1;
+    // Card where the issuer is external.
+    EXTERNAL_ISSUER = 2;
+  }
+  optional Issuer issuer = 1;
+
+  // Uniquely identifies the issuer of the card. This field is required when
+  // Issuer is EXTERNAL_ISSUER.
+  // Example: capitalone, amex.
+  optional string issuer_id = 2;
+}
+
+message WalletMaskedCreditCard {
+  reserved 9, 14;
+  reserved "card_class";
+
+  enum WalletCardStatus {
+    VALID = 0;
+    EXPIRED = 1;
+  }
+
+  enum WalletCardType {
+    UNKNOWN = 0;
+    AMEX = 1;
+    DISCOVER = 2;
+    JCB = 3;
+    MAESTRO = 4;
+    MASTER_CARD = 5;
+    SOLO = 6;
+    SWITCH = 7;
+    VISA = 8;
+    UNIONPAY = 9;
+    ELO = 10;
+    VERVE = 11;
+  }
+
+  enum VirtualCardEnrollmentState {
+    UNSPECIFIED = 0;
+    UNENROLLED = 1 [deprecated = true];
+    ENROLLED = 2;
+    UNENROLLED_AND_NOT_ELIGIBLE = 3;
+    UNENROLLED_AND_ELIGIBLE = 4;
+  }
+
+  enum VirtualCardEnrollmentType {
+    TYPE_UNSPECIFIED = 0;
+    ISSUER = 1;
+    NETWORK = 2;
+  }
+
+  enum CardInfoRetrievalEnrollmentState {
+    RETRIEVAL_UNSPECIFIED = 0;
+    RETRIEVAL_ENROLLED = 1;
+    RETRIEVAL_UNENROLLED_AND_NOT_ELIGIBLE = 2;
+    RETRIEVAL_UNENROLLED_AND_ELIGIBLE = 3;
+  }
+
+  enum CardBenefitSource {
+    SOURCE_UNKNOWN = 0;
+    SOURCE_AMEX = 1;
+    SOURCE_BMO = 2;
+    SOURCE_CURINOS = 3;
+  }
+
+  enum CardCreationSource {
+    CREATION_SOURCE_UNSPECIFIED = 0;
+    CREATION_SOURCE_CHROME_PAYMENTS = 1;
+    CREATION_SOURCE_NON_CHROME_PAYMENTS = 2;
+  }
+
+  // Server-generated unique ID string. This is opaque to the client.
+  // This is the legacy version of `instrument_id`.
+  optional string id = 1;
+
+  // What the server thinks of this card.
+  optional WalletCardStatus status = 2;
+
+  optional string name_on_card = 3;
+
+  optional WalletCardType type = 4;
+
+  // Last 4 digits of the credit card number.
+  optional string last_four = 5;
+
+  // Month number 1-12.
+  optional int32 exp_month = 6;
+
+  // Four-digit year (e.g. 2017).
+  optional int32 exp_year = 7;
+
+  // The WalletPostalAddress.id of the billing address.
+  optional string billing_address_id = 8;
+
+  // Issuing Bank name which is internationalized (e.g. "Chase", "工商银行")
+  optional string bank_name = 10;
+
+  // TODO(crbug.com/40105930): Deprecated, remove this once dependent change is
+  // done.
+  // Use WalletCreditCardCloudTokenData instead. This field will be set if
+  // a cloud token is available for the instrument.
+  optional CloudTokenData cloud_token_data = 11;
+
+  // The card's nickname, if it exists.
+  optional string nickname = 12;
+
+  // Issuer of the card.
+  optional CardIssuer card_issuer = 13;
+
+  // Server-generated unique ID. This is opaque to the client.
+  // `id` is the legacy version of this.
+  optional int64 instrument_id = 15;
+
+  // The state of virtual card enrollment.
+  optional VirtualCardEnrollmentState virtual_card_enrollment_state = 16;
+
+  // The URL for the client to fetch the card art image.
+  optional string card_art_url = 17;
+
+  // The product description for the card. Used to be shown in the UI.
+  optional string product_description = 18;
+
+  // The type of virtual card enrollment. kTypeUnspecified indicates that the
+  // card is unenrolled.
+  optional VirtualCardEnrollmentType virtual_card_enrollment_type = 19;
+
+  // The benefits (e.g. points or discounts) associated with purchases made
+  // with the card.
+  repeated CardBenefit card_benefit = 20;
+
+  // Separate link from the card issuer which provides additional context or
+  // terms and conditions regarding the credit card product and its benefits.
+  optional string product_terms_url = 21;
+
+  // The state of enrollement for runtime card info retrieval. Enrollment in
+  // 'CardInfoRetrieval' will enable runtime retrieval of card information from
+  // card issuer including card number, expiry and CVC.
+  optional CardInfoRetrievalEnrollmentState
+      card_info_retrieval_enrollment_state = 22;
+
+  // The source of the card's benefits. eg: Curinos. Each card can only have one
+  // single benefit source, even if there are multiple benefits.
+  optional CardBenefitSource card_benefit_source = 23;
+
+  // The source of the card creation, indicating whether the card was added
+  // through a Chrome-related service, or through an external service (which
+  // includes Android Autofill).
+  optional CardCreationSource card_creation_source = 24;
+}
+
+// Unused by the client since M121.
+// TODO(crbug.com/40273491): Some server-side code still relies on this message.
+// To keep the protos in sync, it is kept until that code is cleaned up.
+// Different than an AutofillProfile because this represents some known address
+// on the server that is pulled down rather than synced between Chromes.
+message WalletPostalAddress {
+  optional string id = 1;
+
+  optional string recipient_name = 12;
+  optional string company_name = 2;
+
+  // This is the street address, of which there may be multiple lines. This
+  // corresponds to "address_home_line[1|2] in the AutofillProfileSpecifics
+  // message above. In some locales there may be more than two lines.
+  repeated string street_address = 3;
+
+  // Also known as "administrative area". This is normally the state or
+  // province in most countries.
+  optional string address_1 = 4;
+
+  // Also known as "locality". In the US this is the city.
+  optional string address_2 = 5;
+
+  // A sub-classification beneath the city, e.g. an inner-city district or
+  // suburb. Also known as "dependent_locality"
+  optional string address_3 = 6;
+
+  // Used in certain countries. Also known as "sub_dependent_locality".
+  optional string address_4 = 7;
+
+  optional string postal_code = 8;
+
+  // Similar to the zipcode column, but used for businesses or organizations
+  // that might not be geographically contiguous. The canonical example is
+  // CEDEX in France.
+  optional string sorting_code = 9;
+
+  optional string country_code = 10;
+  optional string language_code = 11;
+
+  // Phone number. The format is unspecified and will be explicitly ignored.
+  optional string phone_number = 13;
+}
+
+// Contains information about a Payments Customer.
+message PaymentsCustomerData {
+  // The billable customer ID associated with the account.
+  optional string id = 1;
+}
+
+// Contains information about the cloud token data of server credit cards.
+message WalletCreditCardCloudTokenData {
+  // Server-generated ID string for the card this cloud token data is related
+  // to. This should match the id in WalletMaskedCreditCard for to fetch the
+  // corresponding actual card data. Note this is not unique across all cloud
+  // token data, which means one card can have multiple sets of cloud token data
+  // with the same masked_card_id.
+  optional string masked_card_id = 1;
+
+  // Last 4-5 digits of the Cloud Primary Account Number (CPAN).
+  optional string suffix = 2;
+
+  // CPAN Month number 1-12.
+  optional int32 exp_month = 3;
+
+  // CPAN Four-digit year (e.g. 2017).
+  optional int32 exp_year = 4;
+
+  // URL of the card art to be displayed for CPAN.
+  optional string art_fife_url = 5;
+
+  // Opaque identifier for the cloud token.
+  optional string instrument_token = 6;
+}
+
+// Contains information of payment instruments that can be used by the user.
+message PaymentInstrument {
+  // Opaque identifier for the account stored in Payments Platform.
+  // This will be used to initiate the payment.
+  optional int64 instrument_id = 1;
+
+  // Supported payment infrastructures (rail) that allow users to send money
+  // between the payer and the payee. https://en.wikipedia.org/wiki/Payment_rail
+  enum SupportedRail {
+    SUPPORTED_RAIL_UNKNOWN = 0;
+    // Payment rails for Brazil Open Banking.
+    PIX = 1;
+    // International Bank Account Numbers.
+    IBAN = 2;
+    // This rail can be used for making payments to push payment targets
+    // represented as payment hyperlinks that are supported by the instrument
+    // issuer. The hyperlink will be specified in the href attribute within a
+    // <link> tag in the DOM representing the payment page.
+    // More details on payment links can be found at
+    // https://github.com/aneeshali/paymentlink/blob/main/docs/explainer.md.
+    PAYMENT_HYPERLINK = 3;
+    // This rail is used for making payments via card numbers. Example use case:
+    // Credit/Debit cards, BuyNowPayLater (BNPL), eWallet Fronting cards etc.
+    CARD_NUMBER = 4;
+  }
+  // The supported rails for which a payment can be made for the given account.
+  // For example, Pix is the open-banking rail in Brazil, UPI is the
+  // open-banking rail in India.
+  repeated SupportedRail supported_rails = 2;
+
+  // The URL for the image to be displayed when showing the account to the
+  // user.
+  optional string display_icon_url = 3;
+
+  // Nickname for the instrument.
+  optional string nickname = 4;
+
+  // The backing source for the applicable rails.
+  oneof instrument_details {
+    BankAccountDetails bank_account = 5;
+    WalletMaskedIban iban = 6;
+    EwalletDetails ewallet_details = 7;
+    BnplIssuerDetails bnpl_issuer_details = 9;
+  }
+
+  optional DeviceDetails device_details = 8;
+
+  enum ActionRequired {
+    ACTION_REQUIRED_UNKNOWN = 0;
+    // The user needs to accept the relevant ToS to make the instrument usable.
+    ACCEPT_TOS = 1;
+  }
+
+  // The action to take to update the instrument.
+  repeated ActionRequired action_required = 10;
+}
+
+// Details for user's linked and unlinked Buy Now Pay Later issuers.
+message BnplIssuerDetails {
+  // Unique identifier for the BNPL partner. Example: 'affirm'.
+  optional string issuer_id = 1;
+  // Eligible price range that the BNPL issuer supports.
+  repeated EligiblePriceRange eligible_price_range = 2;
+}
+
+// Details for payment instruments that the user is eligible to create an
+// instrument with.
+message PaymentInstrumentCreationOption {
+  // Identifier for the payment instrument creation option.
+  optional string id = 1;
+
+  oneof creation_option {
+    BnplCreationOption buy_now_pay_later_option = 2;
+  }
+}
+
+// Buy Now Pay Later details that the user is eligible to create an instrument
+// from.
+message BnplCreationOption {
+  // Unique identifier for the BNPL partner. Example: 'affirm'.
+  optional string issuer_id = 1;
+  // Eligible price range that the BNPL issuer supports.
+  repeated EligiblePriceRange eligible_price_range = 2;
+}
+
+// Details the eligible price range that a BNPL issuer supports. Server
+// should set min and max price and ensure that they are both for the same
+// currency.
+message EligiblePriceRange {
+  // Currency of the price range. This field contains a three-letter currency
+  // code.
+  optional string currency = 1;
+  // Min and max eligible price in micros of currency, i.e. one millionths of
+  // the base unit (dollars, not cents for example). e.g. $1.05 == 1050000
+  // micros.
+  optional int64 min_price_in_micros = 2;
+  optional int64 max_price_in_micros = 3;
+}
+
+// Contains information of server IBAN (International Bank Account Number).
+message WalletMaskedIban {
+  // Opaque identifier for the account stored in Payments Platform.
+  optional string instrument_id = 1;
+
+  // Prefix of the full IBAN value, if available.
+  optional string prefix = 2;
+
+  // Suffix of the full IBAN value, if available.
+  optional string suffix = 3;
+
+  // Length of the full IBAN value, if available.
+  optional int32 length = 4;
+
+  // Nickname for the IBAN, if available.
+  optional string nickname = 5;
+}
+
+// Details of a bank account required to show it in the payment instrument
+// selector.
+message BankAccountDetails {
+  // The name of the bank where the user has an account.
+  optional string bank_name = 1;
+
+  // The last four digits of the account number to help the user identify their
+  // account.
+  optional string account_number_suffix = 2;
+
+  enum AccountType {
+    ACCOUNT_TYPE_UNSPECIFIED = 0;
+    CHECKING = 1;
+    SAVINGS = 2;
+    CURRENT = 3;
+    SALARY = 4;
+    TRANSACTING_ACCOUNT = 5;
+  }
+  // The type of bank account.
+  optional AccountType account_type = 3;
+}
+
+// Details of an eWallet account required to show it in the payment instrument
+// selector.
+message EwalletDetails {
+  // Name of the ewallet provider.
+  optional string ewallet_name = 1;
+
+  // Display name of the ewallet account.
+  optional string account_display_name = 2;
+
+  // Payment hyperlinks will be embedded in payment web pages. Chrome will match
+  // the payment link against the list of payment link URI regexes below. If
+  // there is a match, the payment flow will be initiated via the Payments
+  // Server. The regex matching approach makes it possible to launch new payment
+  // methods without requiring any client side changes. More details on payment
+  // links can be found at
+  // https://github.com/aneeshali/paymentlink/blob/main/docs/explainer.md.
+  repeated string supported_payment_link_uris = 3;
+}
+
+// This field captures all of the information related to the instrument-device
+// combo that is required for the payment flows.
+message DeviceDetails {
+  // Whether the device is enrolled in FIDO for this instrument. Depending on
+  // the FIDO state, the Chrome client will show a different UI for the
+  // user. For an unbound device, there will be some user-education content and
+  // the user will be asked to complete FIDO binding. For an already-bound
+  // device, the user will see a more simplified UI.
+  optional bool is_fido_enrolled = 1;
+}
+
+message AutofillWalletSpecifics {
+  enum WalletInfoType {
+    UNKNOWN = 0;
+    MASKED_CREDIT_CARD = 1;
+    // POSTAL_ADDRESS is unused by the client since M121.
+    POSTAL_ADDRESS = 2;
+    CUSTOMER_DATA = 3;
+    CREDIT_CARD_CLOUD_TOKEN_DATA = 4;
+    PAYMENT_INSTRUMENT = 5;
+    MASKED_IBAN = 6 [deprecated = true];
+    PAYMENT_INSTRUMENT_CREATION_OPTION = 7;
+  }
+
+  optional WalletInfoType type = 1;
+
+  // This field exists if and only if the "type" field equals to
+  // MASKED_CREDIT_CARD.
+  optional WalletMaskedCreditCard masked_card = 2;
+
+  // Unused by the client since M121.
+  // This field exists if and only if the `type` equals POSTAL_ADDRESS.
+  // TODO(crbug.com/40273491): Some server-side code still relies on this field.
+  // To keep the protos in sync, it is kept until that code is cleaned up.
+  optional WalletPostalAddress address = 3;
+
+  // This field exists if and only if the "type" field equals to CUSTOMER_DATA.
+  optional PaymentsCustomerData customer_data = 4;
+
+  // This field exists if and only if the "type" field equals to
+  // CREDIT_CARD_CLOUD_TOKEN_DATA.
+  optional WalletCreditCardCloudTokenData cloud_token_data = 5;
+
+  // This field exists if and only if the "type" field equals to
+  // PAYMENT_INSTRUMENT.
+  optional PaymentInstrument payment_instrument = 6;
+
+  // This field exists if and only if the `type` field equals to
+  // MASKED_IBAN.
+  optional WalletMaskedIban masked_iban = 7 [deprecated = true];
+
+  // This field exists if and only if the "type" field equals to
+  // PAYMENT_INSTRUMENT_CREATION_OPTION.
+  optional PaymentInstrumentCreationOption payment_instrument_creation_option =
+      8;
+}
+
+// Wallet card usage information that can be synced.
+message WalletMetadataSpecifics {
+  enum Type {
+    UNKNOWN = 0;
+    CARD = 1;
+    // Unused by the client since M121.
+    // TODO(crbug.com/40273491): Some server-side code still relies on this.
+    // To keep the protos in sync, it is kept until that code is cleaned up.
+    ADDRESS = 2;
+    IBAN = 3;
+  }
+
+  // The type of the Wallet metadata.
+  optional Type type = 1;
+
+  // Base64 encoding of the unique ID string of the corresponding
+  // AutofillMetadata.
+  // For Wallet cards, this value is WalletMaskedCreditCard::id.
+  // For Wallet IBANs, this value is WalletMaskedIban::instrument_id.
+  optional string id = 2;
+
+  // The number of times that this Wallet card or address was used.
+  optional int64 use_count = 3;
+
+  // The last use date of this Wallet card or address. Measured in microseconds
+  // since the Windows epoch (1601).
+  optional int64 use_date = 4;
+
+  // The id of the profile/address that represents the billing address of this
+  // Wallet card.
+  optional string card_billing_address_id = 5;
+
+  // Unused by the client since M121.
+  // TODO(crbug.com/40273491): Some server-side code still relies on this field.
+  // To keep the protos in sync, it is kept until that code is cleaned up.
+  optional bool address_has_converted = 6;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/autofill_valuable_setting_specifics.proto b/pyhindsight/lib/components/sync/protocol/autofill_valuable_setting_specifics.proto
new file mode 100644
index 0000000..ae6a49b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/autofill_valuable_setting_specifics.proto
@@ -0,0 +1,28 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Used to sync settings for `AUTOFILL_VALUABLE`. Since these settings originate
+// from the user's Wallet account settings, they are not reusing standard
+// syncable prefs.
+message AutofillValuableSettingSpecifics {
+  optional string name = 1;
+  // The value of the setting. Which variant is set depends on the setting.
+  oneof Value {
+    bool bool_value = 2;
+    string string_value = 3;
+    int64 int_value = 4;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/autofill_valuable_specifics.proto b/pyhindsight/lib/components/sync/protocol/autofill_valuable_specifics.proto
new file mode 100644
index 0000000..1126227
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/autofill_valuable_specifics.proto
@@ -0,0 +1,121 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// This is a copy of google.protobuf.Any.
+message Any {
+  // A URL/resource name that uniquely identifies the type of the serialized
+  // protocol buffer message.
+  optional string type_url = 1;
+
+  // Must be a valid serialized protocol buffer of the above specified type.
+  optional bytes value = 2;
+}
+
+// Represents a loyalty card from Google Wallet.
+message LoyaltyCard {
+  // The merchant name e.g. "Deutsche Bahn".
+  optional string merchant_name = 1;
+
+  // The program name e.g. "BahnBonus".
+  optional string program_name = 2;
+
+  // The logo URL.
+  optional string program_logo = 3;
+
+  // The loyalty card text code.
+  optional string loyalty_card_number = 4;
+
+  // Merchant domains associated to the loyalty card.
+  repeated string merchant_domains = 5;
+}
+
+// Represents a vehicle registration from Google Wallet.
+message VehicleRegistration {
+  // The vehicle make e.g. "Ford".
+  optional string vehicle_make = 1;
+
+  // The vehicle model e.g. "Fiesta".
+  optional string vehicle_model = 2;
+
+  // The year when model was first made e.g. "2018".
+  optional string vehicle_year = 3;
+
+  // The Vehicle Identification Number (VIN).
+  optional string vehicle_identification_number = 4;
+
+  // The license plate number.
+  optional string vehicle_license_plate = 5;
+
+  // The region that issued the license plate.
+  optional string license_plate_region = 6;
+
+  // The country that issued the license plate, normalized to ISO 3166-1
+  // alpha-2.
+  optional string license_plate_country = 7;
+
+  // The owner of the vehicle as it appears on their vehicle registration
+  // documents.
+  optional string owner_name = 8;
+}
+
+// Represents a flight reservation from Google Wallet.
+message FlightReservation {
+  // The flight number.
+  optional string flight_number = 1;
+
+  // The flight ticket number.
+  optional string flight_ticket_number = 2;
+
+  // The flight confirmation code (normally ~6 digits made of alphanumeric
+  // characters).
+  optional string flight_confirmation_code = 3;
+
+  // The passenger's full name.
+  optional string passenger_name = 4;
+
+  // The departure airport in IATA format e.g AMS for Amsterdam Schiphol.
+  optional string departure_airport = 5;
+
+  // The arrival airport in IATA format e.g LHR for London Heathrow.
+  optional string arrival_airport = 6;
+
+  // The departure date. This is a server-provided timestamp in microseconds.
+  optional int64 departure_date_unix_epoch_micros = 7;
+
+  // The arrival date. This is a server-provided timestamp with units in
+  // microseconds.
+  optional int64 arrival_date_unix_epoch_micros = 8;
+}
+
+// Valuables coming from Google Wallet.
+message AutofillValuableSpecifics {
+  // The valuable id.
+  optional string id = 1;
+
+  // True if the pass is editable by external clients.
+  optional bool is_editable = 6;
+
+  oneof valuable_data {
+    LoyaltyCard loyalty_card = 2;
+    VehicleRegistration vehicle_registration = 3;
+    FlightReservation flight_reservation = 5;
+    // add other valuable types here.
+  }
+
+  // Contains information that is used by Chrome and needs to be persisted
+  // across clients.
+  optional Any serialized_chrome_valuables_metadata = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/autofill_wallet_credential_specifics.proto b/pyhindsight/lib/components/sync/protocol/autofill_wallet_credential_specifics.proto
new file mode 100644
index 0000000..d3dcd94
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/autofill_wallet_credential_specifics.proto
@@ -0,0 +1,27 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Autofill wallet data which stores the relevant card credential data.
+message AutofillWalletCredentialSpecifics {
+  // A server-generated unique ID for the instrument/card.
+  optional string instrument_id = 1;
+
+  // A 3 or 4 digit card verification code.
+  optional string cvc = 2;
+
+  // The timestamp of the last update. Used to determine data freshness.
+  optional int64 last_updated_time_unix_epoch_millis = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/autofill_wallet_usage_specifics.proto b/pyhindsight/lib/components/sync/protocol/autofill_wallet_usage_specifics.proto
new file mode 100644
index 0000000..6d81241
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/autofill_wallet_usage_specifics.proto
@@ -0,0 +1,43 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Autofill usage data related objects which contains usage data of a payment
+// method related to a specific merchant.
+
+message AutofillWalletUsageSpecifics {
+  // A unique ID identifying this item. Used as the client tag.
+  optional string guid = 1;
+
+  // The type of usage data this entity is associated with.
+  oneof usage_data_type {
+    VirtualCardUsageData virtual_card_usage_data = 2;
+  }
+
+  message VirtualCardUsageData {
+    // The instrument id of the actual card that the virtual card is related to.
+    optional int64 instrument_id = 1;
+
+    // The last four of the virtual card number. This is tied to the usage
+    // data because the virtual card number may vary depending on merchants.
+    optional string virtual_card_last_four = 2;
+
+    // The url of the merchant where the virtual card is used.
+    optional string merchant_url = 3;
+
+    // The merchant the usage data is related to on the Android platform.
+    optional string merchant_app_package = 4;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/bookmark_model_metadata.proto b/pyhindsight/lib/components/sync/protocol/bookmark_model_metadata.proto
new file mode 100644
index 0000000..524b00c
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/bookmark_model_metadata.proto
@@ -0,0 +1,79 @@
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/data_type_state.proto";
+import "components/sync/protocol/entity_metadata.proto";
+
+// Corresponds to a single bookmark id/metadata pair.
+message BookmarkMetadata {
+  // Bookmark local id.
+  optional int64 id = 1;
+
+  // Bookmarks sync metadata.
+  optional EntityMetadata metadata = 2;
+}
+
+// Sync proto to carry the sync metadata for the bookmarks model. It is used for
+// persisting and loading sync metadata from disk.
+message BookmarkModelMetadata {
+  // Bookmark global metadata.
+  optional DataTypeState data_type_state = 1;
+
+  // A set of all bookmarks metadata.
+  repeated BookmarkMetadata bookmarks_metadata = 2;
+
+  reserved 3;
+
+  reserved 4;
+
+  reserved 5;
+
+  // Indicates whether the reupload of bookmarks has been triggered such that
+  // they include fields like `type`, `unique_position` and `parent_guid`, which
+  // means that their sequence number has been increased (independently of
+  // whether the commit has succeeded or even started).
+  // TODO(crbug.com/40780588): remove this code when most of bookmarks are
+  // reuploaded.
+  optional bool bookmarks_hierarchy_fields_reuploaded = 6;
+
+  // Number of remote updates that were ignored because the parent folder could
+  // not be determined since sync (bookmark sync) started (since initial sync,
+  // including initial sync itself). Note that this excludes updates
+  // representing changes (moves) to existing/tracked bookmarks (i.e. the parent
+  // folder used to be known, but the new one specified in the update isn't).
+  //
+  // Only a minority of users should have a non-zero value, due to a) corrupt
+  // data, reasons unknown; or b) permanent folders that were unsupported at the
+  // time the update was received (either for the permanent folder itself or for
+  // descendants). The absence of this field should be interpreted as 'unknown',
+  // which roughly means the counter wasn't supported by the browser -M77 or
+  // below- at the time sync was enabled (it also means, it will remain
+  // 'unknown' until initial sync is exercised, e.g. sync disabled and
+  // reenabled).
+  optional int64 num_ignored_updates_due_to_missing_parent = 7;
+
+  // See field above. Among such ignored updates, this field tracks which was
+  // the highest server version. This may be useful -in the future- to get a
+  // sense of "time" (or, since versions are opaque to the client, at least a
+  // notion of ordering with respect to other updates). The absence of this
+  // field should be interpreted as 'unknown' and does not distinguish the
+  // case between a) no updates ignored; and b) field wasn't supported at the
+  // time the last update was ignored. To distinguish between these two, the
+  // field above can be used.
+  optional int64 max_version_among_ignored_updates_due_to_missing_parent = 8;
+
+  // Indicates whether the count of remote updates during the latest initial
+  // merge exceeded the bookmark limit. This field is mutually exclusive to all
+  // the other fields and is managed completely by the processor.
+  optional bool last_initial_merge_remote_updates_exceeded_limit = 9;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/bookmark_specifics.proto b/pyhindsight/lib/components/sync/protocol/bookmark_specifics.proto
new file mode 100644
index 0000000..07df6a5
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/bookmark_specifics.proto
@@ -0,0 +1,95 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for bookmarks.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/unique_position.proto";
+
+// Corresponds to a single meta info key/value pair for a bookmark node.
+message MetaInfo {
+  optional string key = 1;
+  optional string value = 2;
+}
+
+// Properties of bookmark sync objects.
+message BookmarkSpecifics {
+  // URL of the bookmarked page (unset for folders).
+  optional string url = 1;
+  // PNG-encoded content of the favicon image (in practice 16x16, as determined
+  // by `kFaviconSize`). Empty if the bookmark has no favicon (which includes
+  // bookmark folders).
+  optional bytes favicon = 2;
+  // Contains legacy title which is truncated and may contain escaped symbols.
+  optional string legacy_canonicalized_title = 3;
+  // Corresponds to BookmarkNode::date_added() represented as microseconds since
+  // the Windows epoch.
+  optional int64 creation_time_us = 4;
+  // The URL of the favicon image encoded in field `favicon`. Note that there
+  // are various cases where this URL may be missing (field unset or empty) even
+  // if the `favicon` field (image content) is populated:
+  // 1. WebUI pages such as "chrome://bookmarks/" are missing a favicon URL but
+  //    they have a favicon.
+  // 2. Data generated by ancient clients (prior to M25) may not contain the
+  //    favicon URL.
+  // 3. If the favicon URL is too large (determined by `kMaxFaviconUrlSize`) it
+  //    may be omitted by clients to avoid running into the max-entity-size
+  //    limit. Most notably, this includes URLs prefixed with the data: scheme
+  //    that may encode the image content itself in the URL.
+  optional string icon_url = 5;
+  repeated MetaInfo meta_info = 6;
+  reserved 7;
+  reserved 8;
+  reserved 9;
+  // Introduced in M81, it represents a globally unique and immutable ID.
+  //
+  // If present, it must be the same as originator_client_item_id in lowercase,
+  // unless originator client item ID is not a valid GUID. In such cases (which
+  // is the case for bookmarks created before 2015), this GUID must match the
+  // value inferred from the combination of originator cache GUID and
+  // originator client item ID, see InferGuidForLegacyBookmark().
+  //
+  // If not present, the value can be safely inferred using the very same
+  // methods listed above.
+  optional string guid = 10;
+  // Contains full title as is. `legacy_canonicalized_title` is a prefix of
+  // `full_title` with escaped symbols.
+  optional string full_title = 11;
+  reserved 12;
+  reserved 13;
+  // Introduced in M94, represents the GUID (field `guid`) of the parent.
+  optional string parent_guid = 14;
+
+  // Introduced in M94, determines whether this entity represents a bookmark
+  // folder. This field is redundant to the similar field in SyncEntity. If this
+  // field in specifics is set, it takes precedence over the one in SyncEntity.
+  enum Type {
+    // `UNSPECIFIED` is relevant only for the case where the field is not set.
+    // M94 and above should not use this value.
+    UNSPECIFIED = 0;
+    URL = 1;
+    FOLDER = 2;
+  }
+  optional Type type = 15;
+
+  // Introduced in M94, determines ordering among siblings. This field is
+  // redundant to the similar field in SyncEntity. If this field in specifics is
+  // set, it takes precedence over the one in SyncEntity.
+  optional UniquePosition unique_position = 16;
+
+  // Introduced in M106, corresponds to BookmarkNode::date_last_used()
+  // represented as microseconds since the Windows epoch.
+  optional int64 last_used_time_us = 17;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/client_commands.proto b/pyhindsight/lib/components/sync/protocol/client_commands.proto
new file mode 100644
index 0000000..f685619
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/client_commands.proto
@@ -0,0 +1,55 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol for communication between sync client and server.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message CustomNudgeDelay {
+  optional int32 datatype_id = 1;  // Datatype id.
+  optional int32 delay_ms = 2;     // Delay in milliseconds.
+}
+
+message ClientCommand {
+  // Time to wait before sending any requests to the server.
+  optional int32 set_sync_poll_interval = 1;  // in seconds
+  // This has been deprecated since M75.
+  optional int32 set_sync_long_poll_interval = 2 [deprecated = true];
+
+  optional int32 max_commit_batch_size = 3;
+
+  // Number of seconds to delay before the throttled client should retry.
+  optional int32 throttle_delay_seconds = 5;
+
+  // This has been deprecated since M109.
+  optional int32 client_invalidation_hint_buffer_size = 6 [deprecated = true];
+
+  // A dictionary of custom nudge delays.
+  repeated CustomNudgeDelay custom_nudge_delays = 8;
+
+  // Configuration for commit quota of extension-related data types.
+  // The maximum count of tokens (=initial at browser startup) and the
+  // interval for refilling one more token if not at maximum.
+  optional int32 extension_types_max_tokens = 9;
+  optional int32 extension_types_refill_interval_seconds = 10;
+
+  // Extended nudge delay for data types with depleted quota.
+  optional int32 extension_types_depleted_quota_nudge_delay_seconds = 11;
+
+  reserved 4;
+  reserved "sessions_commit_delay_seconds";
+
+  reserved 7;
+  reserved "gu_retry_delay_seconds";
+}
diff --git a/pyhindsight/lib/components/sync/protocol/client_debug_info.proto b/pyhindsight/lib/components/sync/protocol/client_debug_info.proto
new file mode 100644
index 0000000..8f4cb43
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/client_debug_info.proto
@@ -0,0 +1,92 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol for debug info clients can send to the sync server.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/get_updates_caller_info.proto";
+import "components/sync/protocol/sync_enums.proto";
+
+// Per-type hint information.
+message TypeHint {
+  // The data type this hint applied to.
+  optional int32 data_type_id = 1;
+
+  // Whether or not a valid hint is provided.
+  optional bool has_valid_hint = 2;
+}
+
+// The additional info here is from the StatusController. They get sent when
+// the event SYNC_CYCLE_COMPLETED  is sent.
+message SyncCycleCompletedEventInfo {
+  reserved 1;
+  reserved "syncer_stuck";
+  reserved 2;
+  reserved "num_blocking_conflicts";
+  reserved 3;
+  reserved "num_non_blocking_conflicts";
+
+  // These new conflict counters replace the ones above.
+  // TODO(crbug.com/40833583): Deprecated in M103.
+  optional int32 num_encryption_conflicts = 4 [deprecated = true];
+  optional int32 num_hierarchy_conflicts = 5 [deprecated = true];
+  optional int32 num_simple_conflicts = 6;  // No longer sent since M24.
+  optional int32 num_server_conflicts = 7;
+
+  // Counts to track the effective usefulness of our GetUpdate requests.
+  optional int32 num_updates_downloaded = 8;
+  // TODO(crbug.com/40833583): Deprecated in M103.
+  optional int32 num_reflected_updates_downloaded = 9 [deprecated = true];
+
+  // `caller_info` was mostly replaced by `get_updates_origin`; now it only
+  // contains the `notifications_enabled` flag.
+  optional GetUpdatesCallerInfo caller_info = 10;
+
+  // Deprecated in M67.
+  reserved 11;
+  reserved "source_info";
+
+  optional SyncEnums.GetUpdatesOrigin get_updates_origin = 12;
+}
+
+message DebugEventInfo {
+  // Each of the following fields correspond to different kinds of events. as
+  // a result, only one is set during any single DebugEventInfo.
+  // A singleton event. See enum definition.
+  optional SyncEnums.SingletonDebugEventType singleton_event = 1;
+  // A sync cycle completed.
+  optional SyncCycleCompletedEventInfo sync_cycle_completed_event_info = 2;
+  // A datatype triggered a nudge.
+  optional int32 nudging_datatype = 3;
+  // A notification triggered a nudge.
+  repeated int32 datatypes_notified_from_server = 4;
+
+  reserved "datatype_association_stats";
+  reserved 5;
+}
+
+message DebugInfo {
+  repeated DebugEventInfo events = 1;
+
+  // Whether cryptographer is ready to encrypt and decrypt data.
+  optional bool cryptographer_ready = 2;
+
+  // Cryptographer has pending keys which indicates the correct passphrase
+  // has not been provided yet.
+  optional bool cryptographer_has_pending_keys = 3;
+
+  // Indicates client has dropped some events to save bandwidth.
+  optional bool events_dropped = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/collaboration_group_metadata.proto b/pyhindsight/lib/components/sync/protocol/collaboration_group_metadata.proto
new file mode 100644
index 0000000..3734095
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/collaboration_group_metadata.proto
@@ -0,0 +1,23 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// This proto contains metadata about the specific collaboration. Each
+// CollaborationGroupMetadata should be mapped to a specific CollaborationGroup,
+// though the mapping happens outside of Chrome Sync.
+message CollaborationGroupMetadata {
+  // The current version of a collaboration group. This is used for ensuring
+  // that old and new clients can enable or disable functionality based on:
+  // (1) The value of this field.
+  // (2) What that specific version of Chrome supports.
+  optional int64 version = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/collaboration_group_specifics.proto b/pyhindsight/lib/components/sync/protocol/collaboration_group_specifics.proto
new file mode 100644
index 0000000..3bbf035
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/collaboration_group_specifics.proto
@@ -0,0 +1,30 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Special sync datatype to notify client about People Group changes.
+message CollaborationGroupSpecifics {
+  // Unique identifier for a collaboration group, also known as `group_id` or
+  // `group_name`.
+  optional string collaboration_id = 1;
+
+  // Indicates staleness of the collaboration group, used to determine whether
+  // client should refresh cached group. Server-side derived from group event
+  // `changed_at`.
+  optional int64 changed_at_timestamp_millis_since_unix_epoch = 2;
+
+  // An opaque token, that is used to optimize ReadGroup(s) RPCs.
+  optional string consistency_token = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/collaboration_metadata.cc b/pyhindsight/lib/components/sync/protocol/collaboration_metadata.cc
new file mode 100644
index 0000000..9a3979b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/collaboration_metadata.cc
@@ -0,0 +1,111 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/collaboration_metadata.h"
+
+#include <cstddef>
+#include <ostream>
+#include <string>
+
+#include "base/trace_event/memory_usage_estimator.h"
+#include "components/sync/protocol/entity_metadata.pb.h"
+#include "components/sync/protocol/sync_entity.pb.h"
+#include "google_apis/gaia/gaia_id.h"
+
+namespace syncer {
+
+CollaborationMetadata::CollaborationMetadata(
+    const CollaborationMetadata& other) = default;
+CollaborationMetadata& CollaborationMetadata::operator=(
+    const CollaborationMetadata& other) = default;
+CollaborationMetadata::CollaborationMetadata(CollaborationMetadata&& other) =
+    default;
+CollaborationMetadata& CollaborationMetadata::operator=(
+    CollaborationMetadata&& other) = default;
+CollaborationMetadata::~CollaborationMetadata() = default;
+
+// static
+CollaborationMetadata CollaborationMetadata::FromRemoteProto(
+    const sync_pb::SyncEntity::CollaborationMetadata& remote_proto) {
+  return CollaborationMetadata(
+      /*created_by=*/GaiaId(
+          remote_proto.creation_attribution().obfuscated_gaia_id()),
+      /*last_updated_by=*/
+      GaiaId(remote_proto.last_update_attribution().obfuscated_gaia_id()),
+      CollaborationId(remote_proto.collaboration_id()));
+}
+
+// static
+CollaborationMetadata CollaborationMetadata::FromLocalProto(
+    const sync_pb::EntityMetadata::CollaborationMetadata& local_proto) {
+  return CollaborationMetadata(
+      /*created_by=*/GaiaId(
+          local_proto.creation_attribution().obfuscated_gaia_id()),
+      /*last_updated_by=*/
+      GaiaId(local_proto.last_update_attribution().obfuscated_gaia_id()),
+      CollaborationId(local_proto.collaboration_id()));
+}
+
+// static
+CollaborationMetadata CollaborationMetadata::ForLocalChange(
+    const GaiaId& changed_by,
+    const CollaborationId& collaboration_id) {
+  return CollaborationMetadata(
+      /*created_by=*/changed_by,
+      /*last_updated_by=*/changed_by, collaboration_id);
+}
+
+sync_pb::SyncEntity::CollaborationMetadata
+CollaborationMetadata::ToRemoteProto() const {
+  sync_pb::SyncEntity::CollaborationMetadata remote_proto;
+  if (!created_by_.empty()) {
+    remote_proto.mutable_creation_attribution()->set_obfuscated_gaia_id(
+        created_by_.ToString());
+  }
+  if (!last_updated_by_.empty()) {
+    remote_proto.mutable_last_update_attribution()->set_obfuscated_gaia_id(
+        last_updated_by_.ToString());
+  }
+  remote_proto.set_collaboration_id(collaboration_id_.value());
+  return remote_proto;
+}
+
+sync_pb::EntityMetadata::CollaborationMetadata
+CollaborationMetadata::ToLocalProto() const {
+  sync_pb::EntityMetadata::CollaborationMetadata local_proto;
+  if (!created_by_.empty()) {
+    local_proto.mutable_creation_attribution()->set_obfuscated_gaia_id(
+        created_by_.ToString());
+  }
+  if (!last_updated_by_.empty()) {
+    local_proto.mutable_last_update_attribution()->set_obfuscated_gaia_id(
+        last_updated_by_.ToString());
+  }
+  local_proto.set_collaboration_id(collaboration_id_.value());
+  return local_proto;
+}
+
+size_t CollaborationMetadata::EstimateMemoryUsage() const {
+  using base::trace_event::EstimateMemoryUsage;
+  return EstimateMemoryUsage(created_by_.ToString()) +
+         EstimateMemoryUsage(last_updated_by_.ToString()) +
+         EstimateMemoryUsage(collaboration_id_.value());
+}
+
+CollaborationMetadata::CollaborationMetadata(GaiaId created_by,
+                                             GaiaId last_updated_by,
+                                             CollaborationId collaboration_id)
+    : created_by_(std::move(created_by)),
+      last_updated_by_(std::move(last_updated_by)),
+      collaboration_id_(std::move(collaboration_id)) {}
+
+void PrintTo(const CollaborationMetadata& collaboration_metadata,
+             std::ostream* os) {
+  *os << "{ collaboration_id: '"
+      << collaboration_metadata.collaboration_id().value() << "', created_by: '"
+      << collaboration_metadata.created_by() << "', last_updated_by: '"
+      << collaboration_metadata.last_updated_by() << "'}";
+}
+
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/collaboration_metadata.h b/pyhindsight/lib/components/sync/protocol/collaboration_metadata.h
new file mode 100644
index 0000000..f34908e
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/collaboration_metadata.h
@@ -0,0 +1,69 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_COLLABORATION_METADATA_H_
+#define COMPONENTS_SYNC_PROTOCOL_COLLABORATION_METADATA_H_
+
+#include <iosfwd>
+#include <string>
+
+#include "components/sync/base/collaboration_id.h"
+#include "components/sync/protocol/entity_metadata.pb.h"
+#include "components/sync/protocol/sync_entity.pb.h"
+#include "google_apis/gaia/gaia_id.h"
+
+namespace syncer {
+
+// Metadata associated with a shared Sync entity.
+class CollaborationMetadata {
+ public:
+  CollaborationMetadata(const CollaborationMetadata& other);
+  CollaborationMetadata& operator=(const CollaborationMetadata& other);
+  CollaborationMetadata(CollaborationMetadata&& other);
+  CollaborationMetadata& operator=(CollaborationMetadata&& other);
+  ~CollaborationMetadata();
+
+  static CollaborationMetadata FromRemoteProto(
+      const sync_pb::SyncEntity::CollaborationMetadata& remote_metadata);
+  static CollaborationMetadata FromLocalProto(
+      const sync_pb::EntityMetadata::CollaborationMetadata& local_metadata);
+
+  // Creates a CollaborationMetadata for a local change (either creation or
+  // update). For a new entity, `changed_by` will be used for both `created_by`
+  // and `last_updated_by`.
+  static CollaborationMetadata ForLocalChange(
+      const GaiaId& changed_by,
+      const CollaborationId& collaboration_id);
+
+  // The account that created the entity (may be empty).
+  const GaiaId& created_by() const { return created_by_; }
+
+  // The account that last updated the entity (may be empty).
+  const GaiaId& last_updated_by() const { return last_updated_by_; }
+
+  // The collaboration ID of the entity.
+  const CollaborationId& collaboration_id() const { return collaboration_id_; }
+
+  sync_pb::SyncEntity::CollaborationMetadata ToRemoteProto() const;
+  sync_pb::EntityMetadata::CollaborationMetadata ToLocalProto() const;
+
+  size_t EstimateMemoryUsage() const;
+
+ private:
+  CollaborationMetadata(GaiaId created_by,
+                        GaiaId last_updated_by,
+                        CollaborationId collaboration_id);
+
+  GaiaId created_by_;
+  GaiaId last_updated_by_;
+  CollaborationId collaboration_id_;
+};
+
+// gMock printer helper.
+void PrintTo(const CollaborationMetadata& collaboration_metadata,
+             std::ostream* os);
+
+}  // namespace syncer
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_COLLABORATION_METADATA_H_
diff --git a/pyhindsight/lib/components/sync/protocol/collaboration_metadata_unittest.cc b/pyhindsight/lib/components/sync/protocol/collaboration_metadata_unittest.cc
new file mode 100644
index 0000000..b2f9d39
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/collaboration_metadata_unittest.cc
@@ -0,0 +1,68 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/collaboration_metadata.h"
+
+#include "base/test/protobuf_matchers.h"
+#include "components/sync/protocol/entity_metadata.pb.h"
+
+namespace syncer {
+namespace {
+
+using base::test::EqualsProto;
+
+constexpr char kCollaborationId[] = "collaboration";
+constexpr char kCreatorId[] = "creator_id";
+constexpr char kUpdaterId[] = "updater_id";
+
+TEST(CollaborationMetadataTest, SerializeAndDeserializeLocalProto) {
+  sync_pb::EntityMetadata::CollaborationMetadata local_proto;
+  local_proto.set_collaboration_id(kCollaborationId);
+  local_proto.mutable_creation_attribution()->set_obfuscated_gaia_id(
+      kCreatorId);
+  local_proto.mutable_last_update_attribution()->set_obfuscated_gaia_id(
+      kUpdaterId);
+  EXPECT_THAT(CollaborationMetadata::FromLocalProto(local_proto).ToLocalProto(),
+              EqualsProto(local_proto));
+}
+
+TEST(CollaborationMetadataTest, SerializeAndDeserializeRemoteProto) {
+  sync_pb::SyncEntity::CollaborationMetadata remote_proto;
+  remote_proto.set_collaboration_id(kCollaborationId);
+  remote_proto.mutable_creation_attribution()->set_obfuscated_gaia_id(
+      kCreatorId);
+  remote_proto.mutable_last_update_attribution()->set_obfuscated_gaia_id(
+      kUpdaterId);
+  EXPECT_THAT(
+      CollaborationMetadata::FromRemoteProto(remote_proto).ToRemoteProto(),
+      EqualsProto(remote_proto));
+}
+
+TEST(CollaborationMetadataTest, SerializeLocalChangeToProtos) {
+  // Creator and updater are the same for the local change.
+  sync_pb::EntityMetadata::CollaborationMetadata expected_local_proto;
+  expected_local_proto.set_collaboration_id(kCollaborationId);
+  expected_local_proto.mutable_creation_attribution()->set_obfuscated_gaia_id(
+      kCreatorId);
+  expected_local_proto.mutable_last_update_attribution()
+      ->set_obfuscated_gaia_id(kCreatorId);
+
+  sync_pb::SyncEntity::CollaborationMetadata expected_remote_proto;
+  expected_remote_proto.set_collaboration_id(kCollaborationId);
+  expected_remote_proto.mutable_creation_attribution()->set_obfuscated_gaia_id(
+      kCreatorId);
+  expected_remote_proto.mutable_last_update_attribution()
+      ->set_obfuscated_gaia_id(kCreatorId);
+
+  CollaborationMetadata collaboration_metadata =
+      CollaborationMetadata::ForLocalChange(GaiaId(kCreatorId),
+                                            CollaborationId(kCollaborationId));
+  EXPECT_THAT(collaboration_metadata.ToLocalProto(),
+              EqualsProto(expected_local_proto));
+  EXPECT_THAT(collaboration_metadata.ToRemoteProto(),
+              EqualsProto(expected_remote_proto));
+}
+
+}  // namespace
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/contact_info_specifics.proto b/pyhindsight/lib/components/sync/protocol/contact_info_specifics.proto
new file mode 100644
index 0000000..153db0d
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/contact_info_specifics.proto
@@ -0,0 +1,258 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message ContactInfoSpecifics {
+  // Used to distinguish whether the address is the dedicated Home or Work
+  // address of the user's account.
+  // This translates into `AutofillProfile::RecordType::kAccount*`.
+  enum AddressType {
+    REGULAR = 0;
+    HOME = 1;
+    WORK = 2;
+  }
+
+  // Represents the validation status of a stored value.
+  enum VerificationStatus {
+    // No verification status assigned.
+    VERIFICATION_STATUS_UNSPECIFIED = 0;
+    // The value token was parsed from a parent token.
+    // For example, the first name was derived by splitting a full name into
+    // its components.
+    PARSED = 1;
+    // Value was built from its subcomponents.
+    // For example, the full name was built from the first, middle and last
+    // name.
+    FORMATTED = 2;
+    // The value was observed in a form transmission.
+    // For example, the user filled a form that contained at NAME_FULL field.
+    // The value of NAME_FULL will be stored as OBSERVED.
+    OBSERVED = 3;
+    // The user used the settings UI to verify and store this token.
+    // This is currently only applicable to the full name, since users cannot
+    // edit individual components of their name.
+    USER_VERIFIED = 4;
+    // The token was parsed remotely.
+    SERVER_PARSED = 5;
+  }
+
+  message Observation {
+    // An `autofill::ProfileTokenQuality::ObservationType`. Represented as a
+    // uint32 to retain future enum values (since this is proto2).
+    // The `ObservationType`'s underlying type is uint8_t, but this is not
+    // supported by protos. Since the uint32 Proto type uses variable-length
+    // encoding, uint32 has a similar size as a single element byte[].
+    optional uint32 type = 1;
+    // The `autofill::ProfileTokenQuality::FormSignatureHash` has type uint8_t.
+    // Like for `type`, this should have the (non-existing) data type uint8.
+    optional uint32 form_hash = 2;
+  }
+
+  // Metadata that is attached to every token type.
+  message TokenMetadata {
+    optional VerificationStatus status = 1;
+    repeated Observation observations = 2;
+    // Stores a hash of the token value that this metadata is associated with.
+    // This is used by Autofill to detect changes of the token value by external
+    // integrators.
+    optional uint32 value_hash = 3;
+  }
+
+  // A token with a string interpretation of the value.
+  message StringToken {
+    optional string value = 1;
+    optional TokenMetadata metadata = 2;
+  }
+
+  // A globally unique, immutable UUID represented in lowercase.
+  optional string guid = 1;
+  reserved 2;
+  reserved "source";
+  optional AddressType address_type = 56 [default = REGULAR];
+
+  // The number of time this profile has been used.
+  optional int64 use_count = 3;
+
+  // The last times this profile was used. use_date.. is the last use date of
+  // the profile, use_date2.. the second last use date, etc. If a profile hasn't
+  // been used at least that many times, the field is unset.
+  optional int64 use_date_unix_epoch_seconds = 4;
+  optional int64 use_date2_unix_epoch_seconds = 54;
+  optional int64 use_date3_unix_epoch_seconds = 55;
+
+  // The last time the profile was modified.
+  optional int64 date_modified_unix_epoch_seconds = 37;
+
+  // The BCP 47 language code used to format the address for display.
+  optional string language_code = 38;
+
+  // A label intended to be chosen by the user. This was however never
+  // implemented and is currently unused.
+  optional string profile_label = 5;
+
+  // Tracks the application that initially created the profile. The integer
+  // represents a value in the server-side enum `BillableService`. A value of
+  // 70073 represents Chrome (enum value BILLABLE_SERVICE_CHROME_PAYMENTS).
+  optional int32 initial_creator_id = 39;
+  // Tracks the application that applied the last modification to the
+  // non-metadata content of the profile. It represents a value in the same
+  // `BillableService` enum.
+  // All StringTokens, and the `profile_label` are considered non-metadata.
+  optional int32 last_modifier_id = 40;
+
+  // Used to hide account addresses in Chrome.
+  // Chrome will set this value to true if the address should be filtered out
+  // on the server side and not passed to Chrome again.
+  // If Chrome set this value to false or if the value is not set, the address
+  // will be passed to Chrome.
+  optional bool invisible_in_autofill = 62;
+
+  // Contact info name fields.
+  optional StringToken name_first = 7;
+  optional StringToken name_middle = 8;
+  optional StringToken name_last = 9;
+
+  // Prefix of the last name, e.g., "von" in "von Neumann".
+  optional StringToken name_last_prefix = 60;
+
+  // Core of the last name, excluding prefixes.
+  optional StringToken name_last_core = 61;
+
+  // Sometimes the last name is composed of two names as it is common for
+  // Hispanic/Latinx names. In the unstructured representation of the last name,
+  // there may be even a conjunction between the first and the second last
+  // name. For example, the more-complete version of Pablo Picasso's surname is
+  // "Ruiz y Picasso" containing a first last name, a conjunction (the y) and a
+  // second last name.
+  optional StringToken name_last_first = 10;
+  optional StringToken name_last_conjunction = 11;
+  optional StringToken name_last_second = 12;
+  optional StringToken name_full = 13;
+
+  reserved 14;
+  reserved "name_full_with_honorific";
+
+  // Contact info alternative name fields (e.g. phonetic names in Japan).
+  optional StringToken alternative_full_name = 57;
+  optional StringToken alternative_given_name = 58;
+  optional StringToken alternative_family_name = 59;
+
+  // Contact info additional fields.
+  optional StringToken email_address = 15;
+  optional StringToken company_name = 16;
+
+  // Address fields: These are user-provided values with no particular
+  // guarantees about their format.
+  optional StringToken address_city = 17;
+  optional StringToken address_state = 18;
+  optional StringToken address_zip = 19;
+  optional StringToken address_country = 20;
+  optional StringToken address_admin_level_2 = 43;
+
+  // Additional address fields for i18n.
+  // Includes all of the lines of a street address, including newlines, e.g.
+  //   123 Main Street,
+  //   Apt. #42
+  optional StringToken address_street_address = 21;
+  // A sorting code is similar to a postal code. However, whereas a postal code
+  // normally refers to a single geographical location, a sorting code often
+  // does not. Instead, a sorting code is assigned to an organization, which
+  // might be geographically distributed. The most prominent example of a
+  // sorting code system is CEDEX in France.
+  optional StringToken address_sorting_code = 22;
+  // A dependent locality is a subunit of a locality, where a "locality" is
+  // roughly equivalent to a city. Examples of dependent localities include
+  // inner-city districts and suburbs.
+  optional StringToken address_dependent_locality = 23;
+  reserved 24;
+  reserved "address_language_code";
+  // The street name of the address, without a house number.
+  optional StringToken address_thoroughfare_name = 25;
+  // The house number, which may be alphanumeric.
+  optional StringToken address_thoroughfare_number = 26;
+  // Deprecated in M118.
+  reserved 27;
+  reserved "address_dependent_thoroughfare_name";
+  reserved 28;
+  reserved "address_thoroughfare_and_dependent_thoroughfare_name";
+  reserved 29;
+  reserved "address_premise_name";
+  // Contains the floor, staircase or apartment number within a building.
+  optional StringToken address_subpremise_name = 30;
+  // All the information related to the apartment. Normally a combination of the
+  // apartment type (address_apt_type) and number (address_apt_num).
+  // E.g. "Apt 5".
+  optional StringToken address_apt = 50;
+  // The apartment number within a building.
+  optional StringToken address_apt_num = 31;
+  // Information describing the type of apartment (e.g. Apt, Apartamento, Sala,
+  // Departamento).
+  optional StringToken address_apt_type = 51;
+  // The floor number within a building.
+  optional StringToken address_floor = 32;
+  // Contains both the street and house number.
+  optional StringToken address_street_location = 44;
+
+  optional StringToken address_landmark = 41;
+  optional StringToken address_overflow = 45;
+  // Indicates that the address is at the intersection between two streets.
+  // It is normally a combination of between_streets_1 and _2. This is a common
+  // way of writing addresses in Mexico.
+  optional StringToken address_between_streets = 42;
+  // The meaning of the field is similar to address_between_streets. The
+  // type should be used for "Entre calle 1" in MX addresses which also
+  // contain the "Entre calle 2" field.
+  optional StringToken address_between_streets_1 = 46;
+  // The meaning of the field is similar to address_between_streets. The
+  // type should be used for "Entre calle 2" in MX addresses which also
+  // contain the "Entre calle 1" field.
+  optional StringToken address_between_streets_2 = 47;
+  // Combination of types address_between_streets or address_landmark. Note that
+  // some address forms require the combination of both in a single field as
+  // opposed to each one separately.
+  optional StringToken address_between_streets_or_landmark = 48;
+  // Combination of types address_overflow and address_landmark. Note that some
+  // address forms require the combination of both in a single field as opposed
+  // to each one separately.
+  optional StringToken address_overflow_and_landmark = 49;
+  // Combination of types address_street_location and
+  // address_dependent_locality. Note that some address forms require the
+  // combination of both in a single field as opposed to each one separately.
+  optional StringToken address_street_location_and_locality = 52;
+  // Combination of types address_thoroughfare_number and address_apt. Note that
+  // some address forms require the combination of both in a single field as
+  // opposed to each one separately.
+  optional StringToken address_thoroughfare_number_and_apt = 53;
+  // Prefix of the zip code, e.g., "12345" in "12345-6789".
+  optional StringToken address_zip_prefix = 63;
+  // Part of the zip code, excluding prefix and separator.
+  // For example, "6789" in "12345-6789".
+  optional StringToken address_zip_suffix = 64;
+
+  // Phone.
+  optional StringToken phone_home_whole_number = 33;
+
+  // Removed in M123.
+  reserved 34;
+  reserved "birthdate_day";
+  reserved 35;
+  reserved "birthdate_month";
+  reserved 36;
+  reserved "birthdate_year";
+
+  // Removed in M122.
+  reserved 6;
+  reserved "name_honorific";
+}
diff --git a/pyhindsight/lib/components/sync/protocol/cookie_specifics.proto b/pyhindsight/lib/components/sync/protocol/cookie_specifics.proto
new file mode 100644
index 0000000..502a60f
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/cookie_specifics.proto
@@ -0,0 +1,92 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// This proto represents a single cookie. Except for `unique_key` all
+// fields should be the same as in `net::CanonicalCookie`.
+message CookieSpecifics {
+  // To be used as a Sync client tag, corresponds to `StrictlyUniqueCookieKey`.
+  // `StrictlyUniqueCookieKey` contains selected members of
+  // `net::CanonicalCoookie` which we already save in specifics, but we save the
+  // key separately to be resilient against future changes to
+  // `StrictlyUniqueCookieKey`. By reading it from this field (instead of
+  // computing it from other data in specifics) we make sure that the client tag
+  // will be stable across different Chrome versions. It also leaves the option
+  // to check if the key saved in a given entity is aligned with the current
+  // definition of `StrictlyUniqueCookieKey`. If it is not, client can choose to
+  // ignore that entity, or implement any other special handling. The string
+  // saved here is expected to be computed by concatenating serialized values
+  // from the `StrictlyUniqueCookieKey` for the corresponding cookie.
+  optional string unique_key = 1;
+
+  optional string name = 2;
+  optional string value = 3;
+  optional string domain = 4;
+  optional string path = 5;
+
+  optional int64 creation_time_windows_epoch_micros = 6;
+  optional int64 expiry_time_windows_epoch_micros = 7;
+  optional int64 last_access_time_windows_epoch_micros = 8;
+  optional int64 last_update_time_windows_epoch_micros = 9;
+
+  optional bool secure = 10;
+  optional bool httponly = 11;
+
+  // The numbering is different compared to the `net::CookieSameSite` enum since
+  // the style guide asks to use UNSPECIFIED for the zero value enum
+  // (https://protobuf.dev/programming-guides/style/#enums).
+  enum CookieSameSite {
+    UNSPECIFIED = 0;
+    NO_RESTRICTION = 1;
+    LAX_MODE = 2;
+    STRICT_MODE = 3;
+  }
+
+  optional CookieSameSite site_restrictions = 12;
+
+  // The numbering is different compared to the `net::CookiePriority` enum since
+  // the style guide asks to use UNSPECIFIED for the zero value enum
+  // (https://protobuf.dev/programming-guides/style/#enums).
+  enum CookiePriority {
+    UNSPECIFIED_PRIORITY = 0;
+    LOW = 1;
+    MEDIUM = 2;
+    HIGH = 3;
+  }
+
+  optional CookiePriority priority = 13;
+
+  enum CookieSourceScheme {
+    UNSET = 0;
+    NON_SECURE = 1;
+    SECURE = 2;
+  };
+
+  optional CookieSourceScheme source_scheme = 14;
+
+  message SerializedCookiePartitionKey {
+    optional string top_level_site = 1;
+    optional bool has_cross_site_ancestor = 2;
+  }
+
+  optional SerializedCookiePartitionKey partition_key = 15;
+  optional int32 source_port = 16;
+
+  enum CookieSourceType {
+    UNKNOWN = 0;
+    HTTP = 1;
+    SCRIPT = 2;
+    OTHER = 3;
+  };
+
+  optional CookieSourceType source_type = 17;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/data_type_progress_marker.proto b/pyhindsight/lib/components/sync/protocol/data_type_progress_marker.proto
new file mode 100644
index 0000000..bd7cba5
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/data_type_progress_marker.proto
@@ -0,0 +1,183 @@
+// Copyright 2021 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message DataTypeProgressMarker {
+  // An integer identifying the data type whose progress is tracked by this
+  // marker.  The legitimate values of this field correspond to the protobuf
+  // field numbers of all EntitySpecifics fields supported by the server.
+  // These values are externally declared in per-datatype .proto files.
+  optional int32 data_type_id = 1;
+
+  // An opaque-to-the-client sequence of bytes that the server may interpret
+  // as an indicator of the client's knowledge state.  If this is empty or
+  // omitted by the client, it indicates that the client is initiating a
+  // a first-time sync of this datatype.  Otherwise, clients must supply a
+  // value previously returned by the server in an earlier GetUpdatesResponse.
+  // These values are not comparable or generable on the client.
+  //
+  // The opaque semantics of this field are to afford server implementations
+  // some flexibility in implementing progress tracking.  For instance,
+  // a server implementation built on top of a distributed storage service --
+  // or multiple heterogenous such services -- might need to supply a vector
+  // of totally ordered monotonic update timestamps, rather than a single
+  // monotonically increasing value.  Other optimizations may also be
+  // possible if the server is allowed to embed arbitrary information in
+  // the progress token.
+  //
+  // Server implementations should keep the size of these tokens relatively
+  // small, on the order of tens of bytes, and they should remain small
+  // regardless of the number of items synchronized.  (A possible bad server
+  // implementation would be for progress_token to contain a list of all the
+  // items ever sent to the client.  Servers shouldn't do this.)
+  optional bytes token = 2;
+
+  reserved 3;
+  reserved "timestamp_token_for_migration";
+
+  reserved 4;
+  reserved "notification_hint";
+
+  // This field will be included only in GetUpdates with origin GU_TRIGGER.
+  optional GetUpdateTriggers get_update_triggers = 5;
+
+  // The garbage collection directive for this data type.  The client should
+  // purge items locally based on this directive.  Since this directive is
+  // designed to be sent from server only, the client should persist it locally
+  // as needed and avoid sending it to the server.
+  optional GarbageCollectionDirective gc_directive = 6;
+}
+
+// A single datatype's sync context. Allows the datatype to pass along
+// datatype specific information with its own server backend.
+message DataTypeContext {
+  // The type this context is associated with.
+  optional int32 data_type_id = 1;
+  // The context for the datatype.
+  optional bytes context = 2;
+  // The version of the context.
+  optional int64 version = 3;
+}
+
+message GarbageCollectionDirective {
+  enum Type {
+    UNKNOWN = 0;
+    VERSION_WATERMARK = 1;
+    DEPRECATED_AGE_WATERMARK = 2 [deprecated = true];
+    DEPRECATED_MAX_ITEM_COUNT = 3 [deprecated = true];
+  }
+
+  // Deprecated in M124. This field is unused because it would be hard to use
+  // `active_collaboration_ids`. The client should rely on the presence of the
+  // corresponding fields instead.
+  optional Type type = 1 [default = UNKNOWN, deprecated = true];
+
+  // This field specifies the watermark for the versions which should get
+  // garbage collected.  The client should purge all sync entities when
+  // receiving any value of this.  This is a change from previous behavior,
+  // where the client would only be required to purge items older than the
+  // specified watermark.
+  // TODO(crbug.com/41410173): Rename this to make clear that whenever it's set,
+  // the client will delete ALL data, regardless of its value.
+  optional int64 version_watermark = 2;
+
+  reserved 3;
+  reserved "age_watermark_in_days";
+
+  reserved 4;
+  reserved "max_number_of_items";
+
+  // This field contains a list of active collaboration IDs which are available
+  // to the user. The client should stop tracking any shared sync entities with
+  // collaborations which are not in the list. Note that if the list is empty,
+  // an empty `collaboration_gc` is expected to be provided by the server.
+  // Introduced in M124.
+  message CollaborationGarbageCollection {
+    repeated string active_collaboration_ids = 1;
+  }
+  optional CollaborationGarbageCollection collaboration_gc = 5;
+}
+
+// This message communicates additional per-type information related to
+// requests with origin GU_TRIGGER.  This message is not relevant when any
+// other origin value is used.
+// Introduced in M29.
+message GetUpdateTriggers {
+  // An opaque-to-the-client string of bytes, received through a notification,
+  // that the server may interpret as a hint about the location of the latest
+  // version of the data for this type.
+  // Introduced in M29.
+  repeated string notification_hint = 1;
+
+  // This flag is set if the client was forced to drop hints because the number
+  // of queued hints exceeded its limit.  The oldest hints will be discarded
+  // first.  Introduced in M29.
+  optional bool client_dropped_hints = 2;
+
+  // This flag is set when the client suspects that its list of invalidation
+  // hints may be incomplete.  This may be the case if:
+  // - The client is syncing for the first time.
+  // - The client has just restarted and it was unable to keep track of
+  //   invalidations that were received prior to the restart.
+  // - The client's connection to the invalidation server is currently or
+  //   was recently broken.
+  //
+  // It's difficult to provide more details here.  This is implemented by
+  // setting the flag to false whenever anything that might adversely affect
+  // notifications happens (eg. a crash, restart on a platform that doesn't
+  // support invalidation ack-tracking, transient invalidation error) and is
+  // unset only after we've experienced one successful sync cycle while
+  // notifications were enabled.
+  //
+  // This flag was introduced in M29.
+  optional bool invalidations_out_of_sync = 3;
+
+  // This counts the number of times the syncer has been asked to commit
+  // changes for this type since the last successful sync cycle.  The number of
+  // nudges may not be related to the actual number of items modified.  It
+  // often correlates with the number of user actions, but that's not always
+  // the case.
+  // Introduced in M29.
+  optional int64 local_modification_nudges = 4;
+
+  // This counts the number of times the syncer has been explicitly asked to
+  // fetch updates for this type since the last successful sync cycle.  These
+  // explicit refresh requests should be relatively rare on most platforms, and
+  // associated with user actions.  For example, at the time of this writing
+  // the most common (only?) source of refresh requests is when a user opens
+  // the new tab page on a platform that does not support sessions
+  // invalidations.
+  // Introduced in M29.
+  optional int64 datatype_refresh_nudges = 5;
+
+  // This flag is set if the invalidation server reports that it may have
+  // dropped some invalidations at some point.  Introduced in M33.
+  optional bool server_dropped_hints = 6;
+
+  // This flag is set if this GetUpdate request is due at least in part due
+  // to the fact that this type has not finished initial sync yet, and the
+  // client would like to initialize itself with the server data.
+  //
+  // Only some types support performing an initial sync as part of a normal
+  // GetUpdate request.  Many types must be in configure mode when fetching
+  // initial sync data.
+  //
+  // Introduced in M38.
+  optional bool initial_sync_in_progress = 7;
+
+  // This flag is set if this GetUpdate request is due to client receiving
+  // conflict response from server, so client needs to sync and then resolve
+  // conflict locally, and then commit again.
+  //
+  // Introduced in M42.
+  optional bool sync_for_resolve_conflict_in_progress = 8;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/data_type_state.proto b/pyhindsight/lib/components/sync/protocol/data_type_state.proto
new file mode 100644
index 0000000..7dcd3f6
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/data_type_state.proto
@@ -0,0 +1,94 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/data_type_progress_marker.proto";
+
+// Sync proto to store data type global metadata in data type storage.
+message DataTypeState {
+  enum InitialSyncState {
+    // Default value, typically used when there is no metadata (e.g. because
+    // Sync is disabled).
+    INITIAL_SYNC_STATE_UNSPECIFIED = 0;
+
+    // Note: Value "1" is reserved, in case we ever want to introduce an
+    // INITIAL_SYNC_STARTED state.
+
+    // Indicates that syncing has started and some, but not all updates from the
+    // initial download/sync have been delivered. This is only used for data
+    // types in ApplyUpdatesImmediatelyTypes().
+    INITIAL_SYNC_PARTIALLY_DONE = 2;
+
+    // Indicates that the initial sync (download + merge) has been completed.
+    INITIAL_SYNC_DONE = 3;
+
+    // Indicates that no initial sync is necessary, used for CommitOnlyTypes().
+    INITIAL_SYNC_UNNECESSARY = 4;
+  }
+
+  // The latest progress markers received from the server.
+  optional DataTypeProgressMarker progress_marker = 1;
+
+  // A data type context.  Sent to the server in every commit or update
+  // request.  May be updated by either responses from the server or requests
+  // made on the model thread.  The interpretation of this value may be
+  // data-type specific.  Many data types ignore it.
+  optional DataTypeContext type_context = 2;
+
+  // This value is set if this type's data should be encrypted on the server.
+  // If this key changes, the client will need to re-commit all of its local
+  // data to the server using the new encryption key.
+  optional string encryption_key_name = 3;
+
+  // Indicates the status of "initial sync", i.e. whether the first download
+  // cycle and initial merge are complete.
+  optional InitialSyncState initial_sync_state = 9;
+
+  // A GUID that identifies the committing sync client. It's persisted within
+  // the sync metadata and should be used to check the integrity of the
+  // metadata. Mismatches with the guid of the running client indicates invalid
+  // persisted sync metadata, because cache_guid is reset when sync is disabled,
+  // and disabling sync is supposed to clear sync metadata.
+  optional string cache_guid = 5;
+
+  // Syncing account obfuscated Gaia ID, representing the user.
+  optional string authenticated_obfuscated_gaia_id = 6;
+
+  message Invalidation {
+    // Opaque field, which has to be provided as part of resulting GetUpdates
+    // back to the server.
+    optional bytes hint = 1;
+
+    // Version of invalidation, used to order incoming invalidations.
+    optional int64 version = 2;
+  }
+
+  // The latest unprocessed invalidations received from the server.
+  // All incoming invalidations are stored in this message and persist until
+  // they are used in GetUpdate() message.
+  repeated Invalidation invalidations = 7;
+
+  // This is relevant for the passwords datatype. This indicates that the
+  // initial sync flow (downling all passwords from the server) has been run at
+  // least once after the password notes features is enabled. It is used to
+  // enforce redownload of passwords upon upgrading the browser to a version
+  // that supports password notes if necessary. It is false by default and set
+  // to true upon downloading passwords to make sure this download is executed
+  // only once.
+  optional bool notes_enabled_before_initial_sync_for_passwords = 8;
+
+  reserved 4;
+  reserved "initial_sync_done";
+}
diff --git a/pyhindsight/lib/components/sync/protocol/data_type_state_helper.cc b/pyhindsight/lib/components/sync/protocol/data_type_state_helper.cc
new file mode 100644
index 0000000..fdfb1fe
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/data_type_state_helper.cc
@@ -0,0 +1,34 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/data_type_state_helper.h"
+
+#include "components/sync/protocol/data_type_state.pb.h"
+
+namespace syncer {
+
+bool IsInitialSyncDone(sync_pb::DataTypeState::InitialSyncState state) {
+  switch (state) {
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_STATE_UNSPECIFIED:
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_PARTIALLY_DONE:
+      return false;
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_DONE:
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_UNNECESSARY:
+      return true;
+  }
+}
+
+bool IsInitialSyncAtLeastPartiallyDone(
+    sync_pb::DataTypeState::InitialSyncState state) {
+  switch (state) {
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_STATE_UNSPECIFIED:
+      return false;
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_PARTIALLY_DONE:
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_DONE:
+    case sync_pb::DataTypeState_InitialSyncState_INITIAL_SYNC_UNNECESSARY:
+      return true;
+  }
+}
+
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/data_type_state_helper.h b/pyhindsight/lib/components/sync/protocol/data_type_state_helper.h
new file mode 100644
index 0000000..91b243a
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/data_type_state_helper.h
@@ -0,0 +1,23 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_DATA_TYPE_STATE_HELPER_H_
+#define COMPONENTS_SYNC_PROTOCOL_DATA_TYPE_STATE_HELPER_H_
+
+#include "components/sync/base/data_type.h"
+
+namespace sync_pb {
+enum DataTypeState_InitialSyncState : int;
+}  // namespace sync_pb
+
+namespace syncer {
+
+bool IsInitialSyncDone(sync_pb::DataTypeState_InitialSyncState state);
+
+bool IsInitialSyncAtLeastPartiallyDone(
+    sync_pb::DataTypeState_InitialSyncState state);
+
+}  // namespace syncer
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_DATA_TYPE_STATE_HELPER_H_
diff --git a/pyhindsight/lib/components/sync/protocol/data_type_store_schema_descriptor.proto b/pyhindsight/lib/components/sync/protocol/data_type_store_schema_descriptor.proto
new file mode 100644
index 0000000..f1d203b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/data_type_store_schema_descriptor.proto
@@ -0,0 +1,22 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Protocol messages used to record the state of the data type store for USS.
+// At the time of writing, the data type store uses leveldb, a schemaless
+// key-value store. This means that the database's schema is mostly implicit.
+// This descriptor isn't intended to fully describe the schema, just keep track
+// of which major changes have been applied.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message DataTypeStoreSchemaDescriptor {
+  optional int64 version_number = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/deletion_origin.proto b/pyhindsight/lib/components/sync/protocol/deletion_origin.proto
new file mode 100644
index 0000000..e8d3737
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/deletion_origin.proto
@@ -0,0 +1,60 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Protobuf representation of the DeletionOrigin class.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Represents a fingerprint-like token that identifies, or may help identity,
+// which piece of functionality is responsible for issuing a deletion that
+// propagates via Sync. It is sent to the Sync server as part of deletion
+// requests, as a safeguard to investigate and mitigate user reports or even
+// large-scale incidents.
+message DeletionOrigin {
+  // Populated by chromium-based browsers with the version that originally
+  // created the deletion. This will often be the same as the version that
+  // uploaded (committed) the deletion, but in rare cases the latter could be
+  // greater (i.e. the browser was updated in between).
+  optional string chromium_version = 1;
+
+  // Populated by Android Google Play Services with the version of the APK
+  // identifying the version that originally created the deletion. This should
+  // not be populated for DeletionOrigin instances that go through Google Play
+  // Services but were actually first triggered in chromium.
+  optional string google_play_services_apk_version_name = 2;
+
+  // Hash of the filename in the source code where the deletion originated. The
+  // precise hashing function is unspecified and may change over time. It may
+  // only be assumed that the hashing function is the same for a given version
+  // of the client (see fields above). Hashing is used instead of including the
+  // actual name to reduce the size of this message.
+  optional fixed32 file_name_hash = 3;
+
+  // Line of code where the deletion originated.
+  optional int32 file_line_number = 4;
+
+  // Human-readable and extra optional version of `file_name_hash`. Since the
+  // file name can be long and includes the full path, this string is very
+  // likely truncated (and hence not guaranteed to be unique). Truncation will
+  // remove the beginning of the string rather than the end of it.
+  optional string file_name_possibly_truncated = 5;
+
+  // Arbitrary but unique tag defined in the source code, when other means
+  // like the file name and line number aren't possible or desirable. This
+  // string isn't meant to be too long (recommended limit of 30 characters) and
+  // is subject to truncation any time. If truncation is used, it will remove
+  // the beginning of the string rather than the end of it. This field must not
+  // contain personally-identifiable information.
+  optional string unique_source_tag_no_pii_possibly_truncated = 6;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/device_info_specifics.proto b/pyhindsight/lib/components/sync/protocol/device_info_specifics.proto
new file mode 100644
index 0000000..5a2113a
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/device_info_specifics.proto
@@ -0,0 +1,226 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for nigori keys.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/sync_enums.proto";
+
+// Information about a device that is running a sync-enabled Chrome browser.  We
+// are mapping the per-client cache guid to more specific information about the
+// device.
+message DeviceInfoSpecifics {
+  // The cache_guid created to identify a sync client on this device.
+  optional string cache_guid = 1;
+
+  // A non-unique but human readable name to describe this client.
+  optional string client_name = 2;
+
+  // The platform of the device.
+  // Deprecated in M110, but still populated for backwards compatibility.
+  // Replaced by os_type + device_form_factor.
+  optional SyncEnums.DeviceType device_type = 3 [deprecated = true];
+
+  // The UserAgent used when contacting the Chrome Sync server.
+  // Only present when talking to the HTTP server.
+  optional string sync_user_agent = 4;
+
+  // The Chrome instance's version.  Updated (if necessary) on every startup.
+  // DEPRECATED in M92. Still populated for backward compatibility.
+  optional string chrome_version = 5 [deprecated = true];
+
+  // Last time when pre-sync data on the device was saved. The device can be
+  // restored to state back to this time. In millisecond since UNIX epoch.
+  // DEPRECATED in M50.
+  optional int64 deprecated_backup_timestamp = 6 [deprecated = true];
+
+  // Device_id that is stable until user signs out. This device_id is used for
+  // annotating login scoped refresh token. Present only for Chrome Clients.
+  optional string signin_scoped_device_id = 7;
+
+  // This field is updated to be the current time periodically, and is also set
+  // to the current time whenever another field changes. By examining the
+  // difference between this field and the current time, it should be possible
+  // to reason about the inactivity of any device that was syncing at one time.
+  optional int64 last_updated_timestamp = 8;
+
+  // Device info fields that are specific to a feature. This is information that
+  // can not be derived from the other fields in the proto and are not general
+  // enough to be used by another feature.
+  optional FeatureSpecificFields feature_fields = 9;
+
+  // Device specific information for Sharing feature.
+  optional SharingSpecificFields sharing_fields = 10;
+
+  // Model of device.
+  optional string model = 11;
+
+  // Name of device manufacturer.
+  optional string manufacturer = 12;
+
+  // The interval in minutes with which `last_updated_timestamp` is updated to
+  // the sync servers if online and while sync is actively running (e.g.
+  // excludes backgrounded apps on Android). Introduced in M81. The legacy
+  // default was 1 day.
+  optional int32 pulse_interval_in_minutes = 13;
+
+  // Device specific information for Sync invalidations.
+  optional InvalidationSpecificFields invalidation_fields = 14;
+
+  // Information for contacting this device in order to perform security key
+  // operations.
+  optional PhoneAsASecurityKeySpecificFields paask_fields = 15;
+
+  // Unique hardware identifier string which details the HW combination of
+  // a ChromeOS device. This field will be empty on other OS devices.
+  optional string full_hardware_class = 16;
+
+  // Version information to pin-point which client implementation this is.
+  oneof client_version_info {
+    ChromeVersionInfo chrome_version_info = 17;
+    GooglePlayServicesVersionInfo google_play_services_version_info = 18;
+  }
+
+  // The OS type the device.
+  optional SyncEnums.OsType os_type = 19;
+
+  // The form factor of the device.
+  optional SyncEnums.DeviceFormFactor device_form_factor = 20;
+}
+
+// Feature specific information about the device that is running a sync-enabled
+// Chrome browser. Adding to this proto is discouraged and should only be added
+// when the information can not be derived more generally.
+message FeatureSpecificFields {
+  // Tracks whether the SendTabToSelf feature is enabled on the device. For this
+  // to be true, two things must be true: (1) The receiving side of the feature
+  // must be enabled on the device (2) The user has enabled sync for this
+  // feature.
+  optional bool send_tab_to_self_receiving_enabled = 1;
+
+  // Tracks which type of Send Tab To Self message(s) can be sent to the
+  // receiving device.
+  // If not set, the in-app message type will be assumed.
+  optional SyncEnums.SendTabReceivingType send_tab_to_self_receiving_type = 2;
+
+  // Tracks the last time this device signed-in with the Auto Sign-Out
+  // feature enabled. As of 09/2025, this feature is only supported on ChromeOS.
+  optional int64 auto_sign_out_last_signin_timestamp_windows_epoch_micros = 3;
+}
+
+// Device specific information for Sharing feature. Used to send end-to-end
+// encrypted message through FCM or unencrypted message through Chime to other
+// devices.
+message SharingSpecificFields {
+  reserved 1, 2, 3;
+  reserved "vapid_fcm_token", "vapid_p256dh", "vapid_auth_secret";
+
+  // Enum defining available Sharing features.
+  enum EnabledFeatures {
+    reserved 5;
+    reserved "PEER_CONNECTION";
+    reserved 1;
+    reserved "CLICK_TO_CALL_VAPID";
+    reserved 2;
+    reserved "SHARED_CLIPBOARD_VAPID";
+
+    UNKNOWN = 0;
+    SMS_FETCHER = 3;
+    REMOTE_COPY = 4;
+    DISCOVERY = 6;
+    // Supports Click to Call via sender ID.
+    CLICK_TO_CALL_V2 = 7;
+    // Supports Shared Clipboard via sender ID.
+    SHARED_CLIPBOARD_V2 = 8;
+    // Supports optimization guide push notification.
+    OPTIMIZATION_GUIDE_PUSH_NOTIFICATION = 9;
+  }
+
+  // A list of enabled Sharing features.
+  repeated EnabledFeatures enabled_features = 4;
+
+  // Deprecated. Use sender_id_fcm_token_v2 for new clients.
+  optional string sender_id_fcm_token_deprecated = 5 [deprecated = true];
+
+  // Deprecated. Use sender_id_p256dh_v2 for new clients.
+  optional bytes sender_id_p256dh_deprecated = 6 [deprecated = true];
+
+  // Deprecated. Use sender_id_auth_secret_v2 for new clients.
+  optional bytes sender_id_auth_secret_deprecated = 7 [deprecated = true];
+
+  // FCM registration token of device subscribed using Sharing sender ID.
+  optional string sender_id_fcm_token_v2 = 8;
+
+  // Public key for message encryption [RFC8291] using Sharing sender ID.
+  optional bytes sender_id_p256dh_v2 = 9;
+
+  // Auth secret for message encryption [RFC8291] using Sharing sender ID.
+  optional bytes sender_id_auth_secret_v2 = 10;
+
+  // Identifier used to send notifications to a specific device in Chime. Added
+  // in M128.
+  optional string chime_representative_target_id = 11;
+}
+
+// Device specific information telling how to send invalidations to this device.
+message InvalidationSpecificFields {
+  // FCM registration token of device (using Sync sender ID).
+  optional string instance_id_token = 1;
+
+  // This device wants to receive only invalidations which are related to these
+  // types. The legitimate values of this field correspond to the protobuf field
+  // numbers of all EntitySpecifics fields supported by the server (see
+  // components/sync/protocol/sync.proto).
+  repeated int32 interested_data_type_ids = 2;
+}
+
+message PhoneAsASecurityKeySpecificFields {
+  // The encoded tunnel server in the same format as in the BLE advert. See
+  // device::cablev2::tunnelserver::DecodeDomain. (Actually a uint16 but
+  // proto doesn't have that as a type.)
+  optional uint32 tunnel_server_domain = 1;
+
+  // An FCM token that can be presented to the tunnel server to contact this
+  // device.
+  optional bytes contact_id = 2;
+
+  // A shared secret key, used to enable communication across devices via
+  // unauthenticated channels. Knowledge of this secret acts as proof that the
+  // remote end is authorized to talk to the device publishing this secret.
+  optional bytes secret = 3;
+
+  // An id that identifies `secret`. This, and `secret`, will be rotated and
+  // the ID allows this device to know which `secret` the counterparty is
+  // using.
+  optional fixed32 id = 4;
+
+  // A P-256, X9.62-encoded public key for this device. Specific to the Chrome
+  // instance.
+  optional bytes peer_public_key_x962 = 5;
+
+  // The credential ID for use when signing into accounts.google.com. This
+  // credential ID isn't published as a WebauthnCredentialSpecifics, unlike
+  // other passkeys, because it's auto-generated.
+  optional bytes google_credential_id = 6;
+}
+
+message ChromeVersionInfo {
+  // Version number as per https://www.chromium.org/developers/version-numbers.
+  optional string version_number = 1;
+}
+
+message GooglePlayServicesVersionInfo {
+  optional string apk_version_name = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/dictionary_specifics.proto b/pyhindsight/lib/components/sync/protocol/dictionary_specifics.proto
new file mode 100644
index 0000000..f670576
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/dictionary_specifics.proto
@@ -0,0 +1,23 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for the dictionary.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of Dictionary objects.
+message DictionarySpecifics {
+  // A spelling which when typed is treated as a correctly spelled word.
+  optional string word = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/encryption.proto b/pyhindsight/lib/components/sync/protocol/encryption.proto
new file mode 100644
index 0000000..2c7457b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/encryption.proto
@@ -0,0 +1,34 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Common sync protocol for encrypted data.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Encrypted sync data consists of two parts: a key name and a blob. Key name is
+// the name of the key that was used to encrypt blob and blob is encrypted data
+// itself.
+//
+// The reason we need to keep track of the key name is that a sync user can
+// change their passphrase (and thus their encryption key) at any time. When
+// that happens, we make a best effort to reencrypt all nodes with the new
+// passphrase, but since we don't have transactions on the server-side, we
+// cannot guarantee that every node will be reencrypted. As a workaround, we
+// keep track of all keys, assign each key a name (by using that key to encrypt
+// a well known string) and keep track of which key was used to encrypt each
+// node.
+message EncryptedData {
+  optional string key_name = 1;
+  optional string blob = 2;  // base64-encoded.
+}
diff --git a/pyhindsight/lib/components/sync/protocol/entity_data.cc b/pyhindsight/lib/components/sync/protocol/entity_data.cc
new file mode 100644
index 0000000..17a258e
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/entity_data.cc
@@ -0,0 +1,101 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/entity_data.h"
+
+#include <optional>
+#include <ostream>
+#include <string>
+#include <utility>
+
+#include "base/json/json_writer.h"
+#include "base/trace_event/memory_usage_estimator.h"
+#include "base/values.h"
+#include "components/sync/base/time.h"
+#include "components/sync/protocol/proto_memory_estimations.h"
+#include "components/sync/protocol/proto_value_conversions.h"
+
+namespace syncer {
+
+EntityData::EntityData() = default;
+
+EntityData::EntityData(EntityData&& other) = default;
+
+EntityData::~EntityData() = default;
+
+EntityData& EntityData::operator=(EntityData&& other) = default;
+
+base::Value::Dict EntityData::ToDictionaryValue() const {
+  // This is used when debugging at sync-internals page. The code in
+  // sync_node_browser.js is expecting certain fields names. e.g. CTIME, MTIME,
+  // and IS_DIR.
+  base::Value::Dict value =
+      base::Value::Dict()
+          .Set("SPECIFICS", EntitySpecificsToValue(specifics))
+          .Set("ID", id)
+          .Set("CLIENT_TAG_HASH", client_tag_hash.value())
+          .Set("ORIGINATOR_CACHE_GUID", originator_cache_guid)
+          .Set("ORIGINATOR_CLIENT_ITEM_ID", originator_client_item_id)
+          .Set("SERVER_DEFINED_UNIQUE_TAG", server_defined_unique_tag)
+          // The string "NON_UNIQUE_NAME" is used in sync-internals to identify
+          // the node title.
+          .Set("NON_UNIQUE_NAME", name)
+          .Set("NAME", name)
+          // The string "PARENT_ID" is used in sync-internals to build the node
+          // tree.
+          .Set("PARENT_ID", legacy_parent_id)
+          .Set("CTIME", GetTimeDebugString(creation_time))
+          .Set("MTIME", GetTimeDebugString(modification_time))
+          .Set("RECIPIENT_PUBLIC_KEY",
+               CrossUserSharingPublicKeyToValue(recipient_public_key));
+  if (collaboration_metadata.has_value()) {
+    value.Set("COLLABORATION_ID",
+              collaboration_metadata->collaboration_id().value());
+    value.Set("CREATED_BY", collaboration_metadata->created_by().ToString());
+    value.Set("LAST_UPDATED_BY",
+              collaboration_metadata->last_updated_by().ToString());
+  }
+  return value;
+}
+
+size_t EntityData::EstimateMemoryUsage() const {
+  using base::trace_event::EstimateMemoryUsage;
+  size_t memory_usage = 0;
+  memory_usage += EstimateMemoryUsage(id);
+  memory_usage += EstimateMemoryUsage(client_tag_hash);
+  memory_usage += EstimateMemoryUsage(originator_cache_guid);
+  memory_usage += EstimateMemoryUsage(originator_client_item_id);
+  memory_usage += EstimateMemoryUsage(server_defined_unique_tag);
+  memory_usage += EstimateMemoryUsage(name);
+  memory_usage += EstimateMemoryUsage(specifics);
+  memory_usage += EstimateMemoryUsage(legacy_parent_id);
+  memory_usage += EstimateMemoryUsage(recipient_public_key);
+  if (collaboration_metadata.has_value()) {
+    memory_usage += EstimateMemoryUsage(collaboration_metadata.value());
+  }
+  if (deletion_origin.has_value()) {
+    memory_usage += EstimateMemoryUsage(*deletion_origin);
+  }
+  return memory_usage;
+}
+
+void PrintTo(const EntityData& entity_data, std::ostream* os) {
+  std::string specifics;
+  base::JSONWriter::WriteWithOptions(
+      syncer::EntitySpecificsToValue(entity_data.specifics),
+      base::JSONWriter::OPTIONS_PRETTY_PRINT, &specifics);
+  *os << "{ id: '" << entity_data.id << "', client_tag_hash: '"
+      << entity_data.client_tag_hash << "', originator_cache_guid: '"
+      << entity_data.originator_cache_guid << "', originator_client_item_id: '"
+      << entity_data.originator_client_item_id
+      << "', server_defined_unique_tag: '"
+      << entity_data.server_defined_unique_tag << "', specifics: " << specifics;
+  if (entity_data.collaboration_metadata.has_value()) {
+    *os << ", collaboration_metadata: ";
+    PrintTo(entity_data.collaboration_metadata.value(), os);
+  }
+  *os << "}";
+}
+
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/entity_data.h b/pyhindsight/lib/components/sync/protocol/entity_data.h
new file mode 100644
index 0000000..c0159ef
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/entity_data.h
@@ -0,0 +1,114 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_ENTITY_DATA_H_
+#define COMPONENTS_SYNC_PROTOCOL_ENTITY_DATA_H_
+
+#include <iosfwd>
+#include <memory>
+#include <string>
+
+#include "base/time/time.h"
+#include "base/values.h"
+#include "components/sync/base/client_tag_hash.h"
+#include "components/sync/protocol/deletion_origin.pb.h"
+#include "components/sync/protocol/entity_specifics.pb.h"
+#include "components/sync/protocol/collaboration_metadata.h"
+
+namespace syncer {
+
+// A light-weight container for sync entity data which represents either
+// local data created on the local model side or remote data created on
+// DataTypeWorker.
+// EntityData is supposed to be wrapped and passed by reference.
+struct EntityData {
+ public:
+  EntityData();
+
+  EntityData& operator=(const EntityData&) = delete;
+
+  EntityData(EntityData&&);
+  EntityData& operator=(EntityData&&);
+
+  ~EntityData();
+
+  // Typically this is a server assigned sync ID, although for a local change
+  // that represents a new entity this field might be either empty or contain
+  // a temporary client sync ID.
+  std::string id;
+
+  // A hash based on the client tag and data type.
+  // Used for various map lookups. Should always be available for all data types
+  // except bookmarks (for bookmarks it depends on the version of the client
+  // that originally created the bookmark).
+  ClientTagHash client_tag_hash;
+
+  // A GUID that identifies the the sync client who initially committed this
+  // entity. It's relevant only for bookmarks. See the definition in sync.proto
+  // for more details.
+  std::string originator_cache_guid;
+
+  // The local item id of this entry from the client that initially committed
+  // this entity. It's relevant only for bookmarks. See the definition in
+  // sync.proto for more details.
+  std::string originator_client_item_id;
+
+  // This tag identifies this item as being a uniquely instanced item.  An item
+  // can't have both a client_tag_hash and a
+  // server_defined_unique_tag. Sent to the server as
+  // SyncEntity::server_defined_unique_tag.
+  std::string server_defined_unique_tag;
+
+  // Entity name, used mostly for Debug purposes.
+  std::string name;
+
+  // Data type specific sync data.
+  sync_pb::EntitySpecifics specifics;
+
+  // Entity creation and modification timestamps.
+  base::Time creation_time;
+  base::Time modification_time;
+
+  // Server-provided sync ID of the parent entity, used for legacy bookmarks
+  // only. Unused for modern data created or reuploaded by M94 or above, which
+  // relies exclusively on the parent's GUID in BookmarkSpecifics.
+  // WARNING: Avoid references to this field outside
+  // components/sync_bookmarks/parent_guid_preprocessing.cc.
+  std::string legacy_parent_id;
+
+  // Recipient's Public Key used for cross-user sharing data types. Used for
+  // only outgoing password sharing invitations (created locally).
+  sync_pb::CrossUserSharingPublicKey recipient_public_key;
+
+  // Indicate whether bookmark's `unique_position` was missing in the original
+  // specifics during GetUpdates. If the `unique_position` in specifics was
+  // evaluated by AdaptUniquePositionForBookmark(), this field will be set to
+  // true. Relevant only for bookmarks.
+  bool is_bookmark_unique_position_in_specifics_preprocessed = false;
+
+  // Collaboration metadata for the entity. Present only for shared entities.
+  std::optional<CollaborationMetadata> collaboration_metadata;
+
+  // True if EntityData represents deleted entity; otherwise false.
+  // Note that EntityData would be considered to represent a deletion if its
+  // specifics hasn't been set.
+  bool is_deleted() const { return specifics.ByteSizeLong() == 0; }
+
+  // Optionally populated for outgoing deletions. See corresponding field in
+  // SyncEntity for details.
+  std::optional<sync_pb::DeletionOrigin> deletion_origin;
+
+  // Dumps all info into a base::Value::Dict and returns it.
+  base::Value::Dict ToDictionaryValue() const;
+
+  // Returns the estimate of dynamically allocated memory in bytes.
+  size_t EstimateMemoryUsage() const;
+};
+
+// gMock printer helper.
+void PrintTo(const EntityData& entity_data, std::ostream* os);
+
+}  // namespace syncer
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_ENTITY_DATA_H_
diff --git a/pyhindsight/lib/components/sync/protocol/entity_data_unittest.cc b/pyhindsight/lib/components/sync/protocol/entity_data_unittest.cc
new file mode 100644
index 0000000..f138944
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/entity_data_unittest.cc
@@ -0,0 +1,27 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/entity_data.h"
+
+#include "components/sync/base/data_type.h"
+#include "components/sync/base/unique_position.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace syncer {
+
+class EntityDataTest : public testing::Test {
+ protected:
+  EntityDataTest() = default;
+  ~EntityDataTest() override = default;
+};
+
+TEST_F(EntityDataTest, IsDeleted) {
+  EntityData data;
+  EXPECT_TRUE(data.is_deleted());
+
+  AddDefaultFieldValue(BOOKMARKS, &data.specifics);
+  EXPECT_FALSE(data.is_deleted());
+}
+
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/entity_metadata.proto b/pyhindsight/lib/components/sync/protocol/entity_metadata.proto
new file mode 100644
index 0000000..9a3e496
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/entity_metadata.proto
@@ -0,0 +1,117 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+package sync_pb;
+
+import "components/sync/protocol/deletion_origin.proto";
+import "components/sync/protocol/entity_specifics.proto";
+import "components/sync/protocol/unique_position.proto";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+option optimize_for = LITE_RUNTIME;
+
+// Sync proto to store entity metadata in data type storage.
+message EntityMetadata {
+  // A hash based on the client tag and data type.
+  // Used for various map lookups. Should always be available.
+  // Sent to the server as SyncEntity::client_tag_hash.
+  optional string client_tag_hash = 1;
+
+  // The entity's server-assigned ID.
+  //
+  // Prior to the item's first commit, we leave this value as an empty string.
+  // The initial ID for a newly created item has to meet certain uniqueness
+  // requirements, and we handle those on the sync thread.
+  optional string server_id = 2;
+
+  // Whether or not the entity is deleted.
+  optional bool is_deleted = 3;
+
+  // A version number used to track in-progress commits. Each local change
+  // increments this number.
+  optional int64 sequence_number = 4;
+
+  // The sequence number of the last item known to be successfully committed.
+  optional int64 acked_sequence_number = 5;
+
+  // The server version on which this item is based.
+  //
+  // If there are no local changes, this is the version of the entity as we see
+  // it here.
+  //
+  // If there are local changes, this is the version of the entity on which
+  // those changes are based.
+  optional int64 server_version = 6 [default = -1];
+
+  // Entity creation and modification timestamps. Assigned by the client and
+  // synced by the server, though the server usually doesn't bother to inspect
+  // their values. They are encoded as milliseconds since the Unix epoch.
+  optional int64 creation_time = 7;
+  optional int64 modification_time = 8;
+
+  // A hash of the current entity specifics value. Used to detect whether
+  // entity's specifics value has changed without having to keep specifics in
+  // memory.
+  optional string specifics_hash = 9;
+
+  // A hash of the last specifics known by both the client and server. Used to
+  // detect when local commits and remote updates are just for encryption. This
+  // value will be the empty string only in the following cases: the entity is
+  // in sync with the server, has never been synced, or is deleted.
+  optional string base_specifics_hash = 10;
+
+  // Used for positioning entities among their siblings. Relevant only for data
+  // types that support positions (e.g bookmarks). Refer to its definition in
+  // unique_position.proto for more information about its internal
+  // representation.
+  optional UniquePosition unique_position = 11;
+
+  // Used only for bookmarks. It's analogous to `specifics_hash` but it
+  // exclusively hashes the content of the favicon image, as represented in
+  // proto field BookmarkSpecifics.favicon, using base::PersistentHash().
+  optional fixed32 bookmark_favicon_hash = 12;
+
+  // Last specifics known by both the client and server. Used during commits to
+  // the server in order to prevent data loss caused by older clients dealing
+  // with unknown proto fields (fields that were introduced later). Datatypes
+  // (DataTypeSyncBridge) may implement logic to trim down (or fully clear)
+  // this proto prior to caching, to avoid the memory and I/O overhead of
+  // dealing with an extra copy of the data. Introduced in M101.
+  optional EntitySpecifics possibly_trimmed_base_specifics = 13;
+
+  // If the entity is deleted, this field will record the chromium version
+  // (e.g. 117.0.5875.1) that originated the deletion. Introduced in M117.
+  optional string deleted_by_version = 14;
+
+  // Metadata used for shared data types. Must not be present for regular data
+  // types.
+  // Introduced in M124.
+  message CollaborationMetadata {
+    message Attribution {
+      // Obfuscated Gaia ID of the user.
+      optional string obfuscated_gaia_id = 1;
+    }
+
+    // Collaboration ID which the current entity belongs to.
+    optional string collaboration_id = 1;
+
+    // Information about when the specifics was created.
+    optional Attribution creation_attribution = 2;
+
+    // Information about when the specifics was last updated.
+    optional Attribution last_update_attribution = 3;
+  }
+  optional CollaborationMetadata collaboration = 15;
+
+  // Optionally present for committed deletions (but may remain unset if the
+  // origin is unspecified), it represents which piece of code triggered a
+  // deletion. Introduced in M126.
+  optional DeletionOrigin deletion_origin = 16;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/entity_specifics.proto b/pyhindsight/lib/components/sync/protocol/entity_specifics.proto
new file mode 100644
index 0000000..70bc6fd
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/entity_specifics.proto
@@ -0,0 +1,199 @@
+// Copyright 2021 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/encryption.proto";
+import "components/sync/protocol/app_list_specifics.proto";
+import "components/sync/protocol/app_setting_specifics.proto";
+import "components/sync/protocol/app_specifics.proto";
+import "components/sync/protocol/arc_package_specifics.proto";
+import "components/sync/protocol/autofill_specifics.proto";
+import "components/sync/protocol/autofill_offer_specifics.proto";
+import "components/sync/protocol/autofill_valuable_specifics.proto";
+import "components/sync/protocol/autofill_valuable_setting_specifics.proto";
+import "components/sync/protocol/autofill_wallet_credential_specifics.proto";
+import "components/sync/protocol/autofill_wallet_usage_specifics.proto";
+import "components/sync/protocol/bookmark_specifics.proto";
+import "components/sync/protocol/collaboration_group_specifics.proto";
+import "components/sync/protocol/product_comparison_specifics.proto";
+import "components/sync/protocol/contact_info_specifics.proto";
+import "components/sync/protocol/cookie_specifics.proto";
+import "components/sync/protocol/device_info_specifics.proto";
+import "components/sync/protocol/dictionary_specifics.proto";
+import "components/sync/protocol/extension_setting_specifics.proto";
+import "components/sync/protocol/extension_specifics.proto";
+import "components/sync/protocol/history_delete_directive_specifics.proto";
+import "components/sync/protocol/history_specifics.proto";
+import "components/sync/protocol/managed_user_setting_specifics.proto";
+import "components/sync/protocol/managed_user_shared_setting_specifics.proto";
+import "components/sync/protocol/nigori_specifics.proto";
+import "components/sync/protocol/os_preference_specifics.proto";
+import "components/sync/protocol/os_priority_preference_specifics.proto";
+import "components/sync/protocol/password_sharing_invitation_specifics.proto";
+import "components/sync/protocol/password_specifics.proto";
+import "components/sync/protocol/plus_address_setting_specifics.proto";
+import "components/sync/protocol/plus_address_specifics.proto";
+import "components/sync/protocol/preference_specifics.proto";
+import "components/sync/protocol/printer_specifics.proto";
+import "components/sync/protocol/printers_authorization_server_specifics.proto";
+import "components/sync/protocol/priority_preference_specifics.proto";
+import "components/sync/protocol/reading_list_specifics.proto";
+import "components/sync/protocol/saved_tab_group_specifics.proto";
+import "components/sync/protocol/search_engine_specifics.proto";
+import "components/sync/protocol/security_event_specifics.proto";
+import "components/sync/protocol/send_tab_to_self_specifics.proto";
+import "components/sync/protocol/session_specifics.proto";
+import "components/sync/protocol/shared_comment_specifics.proto";
+import "components/sync/protocol/shared_tab_group_data_specifics.proto";
+import "components/sync/protocol/sharing_message_specifics.proto";
+import "components/sync/protocol/theme_specifics.proto";
+import "components/sync/protocol/typed_url_specifics.proto";
+import "components/sync/protocol/user_consent_specifics.proto";
+import "components/sync/protocol/user_event_specifics.proto";
+import "components/sync/protocol/web_apk_specifics.proto";
+import "components/sync/protocol/web_app_specifics.proto";
+import "components/sync/protocol/webauthn_credential_specifics.proto";
+import "components/sync/protocol/wifi_configuration_specifics.proto";
+import "components/sync/protocol/workspace_desk_specifics.proto";
+import "components/sync/protocol/shared_tab_group_account_data_specifics.proto";
+
+message EntitySpecifics {
+  // If a datatype is encrypted, this field will contain the encrypted
+  // original EntitySpecifics. The extension for the datatype will continue
+  // to exist, but contain only the default values.
+  // Note that currently passwords employ their own legacy encryption scheme and
+  // do not use this field.
+  optional EncryptedData encrypted = 1;
+
+  // To add new datatype-specific fields to the protocol, extend
+  // EntitySpecifics.  First, pick a non-colliding tag number by
+  // picking a Cr-Commit-Position of one of your past commits
+  // to src.chromium.org.  Then, in a different protocol buffer
+  // definition, define your message type, and add an optional field
+  // to the list below using the unique tag value you selected.
+  //
+  //  optional MyDatatypeSpecifics my_datatype = 32222;
+  //
+  // where:
+  //   - 32222 is the non-colliding tag number you picked earlier.
+  //   - MyDatatypeSpecifics is the type (probably a message type defined
+  //     in your new .proto file) that you want to associate with each
+  //     object of the new datatype.
+  //   - my_datatype is the field identifier you'll use to access the
+  //     datatype specifics from the code.
+  //
+  // Server implementations are obligated to preserve the contents of
+  // EntitySpecifics when it contains unrecognized fields.  In this
+  // way, it is possible to add new datatype fields without having
+  // to update the server.
+  //
+  // Note: The tag selection process is based on legacy versions of the
+  // protocol which used protobuf extensions. We have kept the process
+  // consistent as the old values cannot change.  The 5+ digit nature of the
+  // tags also makes them recognizable (individually and collectively) from
+  // noise in logs and debugging contexts, and creating a divergent subset of
+  // tags would only make things a bit more confusing.
+
+  oneof specifics_variant {
+    AutofillSpecifics autofill = 31729;
+    BookmarkSpecifics bookmark = 32904;
+    PreferenceSpecifics preference = 37702;
+    ThemeSpecifics theme = 41210;
+    PasswordSpecifics password = 45873;
+    NigoriSpecifics nigori = 47745;
+    ExtensionSpecifics extension = 48119;
+    AppSpecifics app = 48364;
+    SessionSpecifics session = 50119;
+    AutofillProfileSpecifics autofill_profile = 63951;
+    SearchEngineSpecifics search_engine = 88610;
+    ExtensionSettingSpecifics extension_setting = 96159;
+    AppSettingSpecifics app_setting = 103656;
+    HistoryDeleteDirectiveSpecifics history_delete_directive = 150251;
+    DeviceInfoSpecifics device_info = 154522;
+    PriorityPreferenceSpecifics priority_preference = 163425;
+    DictionarySpecifics dictionary = 170540;
+    ManagedUserSettingSpecifics managed_user_setting = 186662;
+    AppListSpecifics app_list = 229170;
+    AutofillWalletSpecifics autofill_wallet = 306270;
+    WalletMetadataSpecifics wallet_metadata = 330441;
+    ArcPackageSpecifics arc_package = 340906;
+    PrinterSpecifics printer = 410745;
+    ReadingListSpecifics reading_list = 411028;
+    UserEventSpecifics user_event = 455206;
+    UserConsentSpecifics user_consent = 556014;
+    SendTabToSelfSpecifics send_tab_to_self = 601980;
+    SecurityEventSpecifics security_event = 600372;
+    WebApkSpecifics web_apk = 1117170;
+    WebAppSpecifics web_app = 673225;
+    WifiConfigurationSpecifics wifi_configuration = 662827;
+    OsPreferenceSpecifics os_preference = 702141;
+    OsPriorityPreferenceSpecifics os_priority_preference = 703915;
+    SharingMessageSpecifics sharing_message = 728866;
+    AutofillOfferSpecifics autofill_offer = 774329;
+    WorkspaceDeskSpecifics workspace_desk = 874841;
+    WebauthnCredentialSpecifics webauthn_credential = 895275;
+    HistorySpecifics history = 963985;
+    PrintersAuthorizationServerSpecifics printers_authorization_server = 974304;
+    SavedTabGroupSpecifics saved_tab_group = 1004874;
+    AutofillWalletUsageSpecifics autofill_wallet_usage = 1033580;
+    ContactInfoSpecifics contact_info = 1034378;
+    IncomingPasswordSharingInvitationSpecifics
+        incoming_password_sharing_invitation = 1141935;
+    OutgoingPasswordSharingInvitationSpecifics
+        outgoing_password_sharing_invitation = 1142081;
+    AutofillWalletCredentialSpecifics autofill_wallet_credential = 1164238;
+    SharedTabGroupDataSpecifics shared_tab_group_data = 1239418;
+    CollaborationGroupSpecifics collaboration_group = 1259076;
+    ProductComparisonSpecifics product_comparison = 1329438;
+    PlusAddressSpecifics plus_address = 1267844;
+    CookieSpecifics cookie = 1281100;
+    PlusAddressSettingSpecifics plus_address_setting = 1303742;
+    AutofillValuableSpecifics autofill_valuable = 1419865;
+    SharedTabGroupAccountDataSpecifics shared_tab_group_account_data = 1429255;
+    SharedCommentSpecifics shared_comment = 1484017;
+    AutofillValuableSettingSpecifics autofill_valuable_setting = 1438954;
+    // When adding a new type, follow the docs below and keep this comment as
+    // the last entry.
+    // https://www.chromium.org/developers/design-documents/sync/integration-checklist/
+
+    // No-longer-supported data types, in various stages of removal.
+    // TODO(crbug.com/40881888): Eventually, these should all become "reserved"
+    // fields, or at least use "EmptySpecifics". But some of them are still
+    // needed by the server, e.g. to support older clients.
+    EmptySpecifics app_notification = 45184 [deprecated = true];
+    EmptySpecifics synced_notification = 153108 [deprecated = true];
+    EmptySpecifics synced_notification_app_info = 235816 [deprecated = true];
+    EmptySpecifics managed_user = 194582 [deprecated = true];
+    ManagedUserSharedSettingSpecifics managed_user_shared_setting = 202026
+        [deprecated = true];
+    EmptySpecifics managed_user_allowlist = 306060 [deprecated = true];
+    TypedUrlSpecifics typed_url = 40781 [deprecated = true];
+  }
+  reserved 161496;
+  reserved "experiments";
+  reserved 181534;
+  reserved "favicon_tracking";
+  reserved 182019;
+  reserved "favicon_image";
+  reserved 218175;
+  reserved "wifi_credential";
+  reserved 223759;
+  reserved "article";
+  reserved 545005;
+  reserved "mountain_share";
+  reserved 1026052;
+  reserved "segmentation";
+  reserved 1073150;
+  reserved "power_bookmark";
+}
+
+message EmptySpecifics {}
diff --git a/pyhindsight/lib/components/sync/protocol/extension_setting_specifics.proto b/pyhindsight/lib/components/sync/protocol/extension_setting_specifics.proto
new file mode 100644
index 0000000..d6c4958
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/extension_setting_specifics.proto
@@ -0,0 +1,29 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for an extension setting.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of extension setting sync objects.
+message ExtensionSettingSpecifics {
+  // Id of the extension the setting is for.
+  optional string extension_id = 1;
+
+  // Setting key.
+  optional string key = 2;
+
+  // Setting value serialized as JSON.
+  optional string value = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/extension_specifics.proto b/pyhindsight/lib/components/sync/protocol/extension_specifics.proto
new file mode 100644
index 0000000..e72c9d7
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/extension_specifics.proto
@@ -0,0 +1,64 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for extensions.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of extension sync objects.
+//
+// Merge policy: the settings for the higher version number win; in
+// the case of a tie, server wins.
+message ExtensionSpecifics {
+  // Globally unique id for this extension.
+  optional string id = 1;
+  // The known installed version.
+  optional string version = 2;
+
+  // Auto-update URL to use for this extension.  May be blank, in
+  // which case the default one (i.e., the one for the Chrome
+  // Extensions Gallery) is used.
+  optional string update_url = 3;
+  // Whether or not this extension is enabled.
+  // TODO(crbug.com/40554334): Deprecate this field. Enabled state can be
+  // determined from the disable reasons set.
+  optional bool enabled = 4;
+  // Whether or not this extension is enabled in incognito mode.
+  optional bool incognito_enabled = 5;
+
+  // DEPRECATED. See https://crbug.com/1233303.
+  optional string name = 6 [deprecated = true];
+
+  // Whether this extension was installed remotely, and hasn't been approved by
+  // a user in chrome yet.
+  optional bool remote_install = 7;
+
+  // DEPRECATED. See https://crbug.com/1014183.
+  optional bool installed_by_custodian = 8 [deprecated = true];
+
+  // DEPRECATED. See https://crbug.com/839681.
+  optional bool all_urls_enabled = 9 [deprecated = true];
+
+  // Bitmask of the set of reasons why the extension is disabled (see
+  // extensions::disable_reason::DisableReason). Only relevant when enabled ==
+  // false. Note that old clients (<M45) won't set this, even when enabled is
+  // false. This will be deprecated in favor of disable_reasons_list. See
+  // crbug.com/372186532.
+  optional int32 disable_reasons = 10;
+
+  // List of reasons why the extension is disabled. Only relevant when enabled
+  // == false. The bitmask above will be deprecated in favor of this field. See
+  // crbug.com/372186532.
+  repeated int32 disable_reasons_list = 11;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/gaia_password_reuse.proto b/pyhindsight/lib/components/sync/protocol/gaia_password_reuse.proto
new file mode 100644
index 0000000..29d32e6
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/gaia_password_reuse.proto
@@ -0,0 +1,105 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Security Events used for recording security related events.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// User reused their GAIA password on another website.
+message GaiaPasswordReuse {
+  // Logged when we detect a password re-use event on a non-GAIA site.
+  // If the user hasn’t enabled SafeBrowsing, this will be the last event.
+  message PasswordReuseDetected {
+    message SafeBrowsingStatus {
+      // Is SafeBrowsing enabled?
+      optional bool enabled = 1;
+      // If SafeBrowsing is enabled, is the user opted-in to extended
+      // reporting or Scout?
+      enum ReportingPopulation {
+        REPORTING_POPULATION_UNSPECIFIED = 0;
+        NONE = 1;
+        EXTENDED_REPORTING = 2;
+        SCOUT = 3;
+        ENHANCED_PROTECTION = 4;
+      }
+      optional ReportingPopulation safe_browsing_reporting_population = 2;
+    }
+    optional SafeBrowsingStatus status = 1;
+  }
+  optional PasswordReuseDetected reuse_detected = 1;
+
+  message PasswordReuseLookup {
+    enum LookupResult {
+      UNSPECIFIED = 0;
+      // URL did match the password reuse allowlist.
+      // No further action required related to this re-use event.
+      ALLOWLIST_HIT = 1;
+      // The URL exists in the client’s cache.
+      // No further action required related to this re-use event.
+      // This event also logs the ReputationVerdict.
+      CACHE_HIT = 2;
+      // A valid response received from the SafeBrowsing service.
+      // This event also logs the ReputationVerdict.
+      REQUEST_SUCCESS = 3;
+      // Unable to get a valid response from the SafeBrowsing service.
+      REQUEST_FAILURE = 4;
+      // We won't be able to compute reputation for the URL e.g. local IP
+      // address, localhost, not-yet-assigned by ICANN gTLD, etc.
+      URL_UNSUPPORTED = 5;
+      // URL did match enterprise allowlist.
+      // No further action required related to this re-use event.
+      ENTERPRISE_ALLOWLIST_HIT = 6;
+      // Password reuse lookup is turned off by enterprise policy.
+      // No further action required related to this re-use event.
+      TURNED_OFF_BY_POLICY = 7;
+    }
+    optional LookupResult lookup_result = 1;
+
+    // The following two are only present for CACHE_HIT and REQUEST_SUCCESS.
+    // The verdict received from the Reputation service. This is set only
+    // if the user has SafeBrowsing enabled and we fetch the verdict from the
+    // cache or by sending a verdict request.
+    enum ReputationVerdict {
+      VERDICT_UNSPECIFIED = 0;
+      SAFE = 1;
+      LOW_REPUTATION = 2;
+      PHISHING = 3;
+    }
+    optional ReputationVerdict verdict = 2;
+    // PhishGuard token that identifies the verdict on the server.
+    optional bytes verdict_token = 3;
+  }
+  // Logged when we try to detect whether the password was reused on a
+  // Phishing or a Low-reputation site.
+  optional PasswordReuseLookup reuse_lookup = 2;
+
+  // Logged when the user interacts with the warning UI shown to encourage
+  // password change if the site is Phishing or Low-reputation.
+  message PasswordReuseDialogInteraction {
+    enum InteractionResult {
+      UNSPECIFIED = 0;
+      // The user took the action suggested by the warning prompt.
+      WARNING_ACTION_TAKEN = 1;
+      // The user clicked ignore in the warning prompt.
+      WARNING_ACTION_IGNORED = 2;
+      // The warning UI was ignored, i.e. not interacted with by the user.
+      // This could happen if the user navigates away from the page.
+      WARNING_UI_IGNORED = 3;
+      // The user clicked "Change Password" on chrome://settings page.
+      WARNING_ACTION_TAKEN_ON_SETTINGS = 4;
+    }
+    optional InteractionResult interaction_result = 1;
+  }
+  optional PasswordReuseDialogInteraction dialog_interaction = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/get_updates_caller_info.proto b/pyhindsight/lib/components/sync/protocol/get_updates_caller_info.proto
new file mode 100644
index 0000000..4388163
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/get_updates_caller_info.proto
@@ -0,0 +1,25 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message GetUpdatesCallerInfo {
+  reserved 1;
+  reserved "source";
+
+  // True if notifications were enabled for this GetUpdateMessage.
+  // Note: Ideally this would be moved out of GetUpdatesCallerInfo, so that
+  // GetUpdatesCallerInfo itself can be removed.
+  optional bool notifications_enabled = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/history_delete_directive_specifics.proto b/pyhindsight/lib/components/sync/protocol/history_delete_directive_specifics.proto
new file mode 100644
index 0000000..61ab8b6
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/history_delete_directive_specifics.proto
@@ -0,0 +1,75 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for history delete directives.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// All timestamps below are from Sane Time (
+// http://www.chromium.org/developers/design-documents/sane-time )
+// and are in microseconds since the Unix epoch.
+
+// Properties of history delete directive sync objects.
+message HistoryDeleteDirectiveSpecifics {
+  oneof directive_type {
+    GlobalIdDirective global_id_directive = 1;
+    TimeRangeDirective time_range_directive = 2;
+    UrlDirective url_directive = 3;
+  }
+}
+
+message GlobalIdDirective {
+  // The global IDs of the navigations to delete.
+  repeated int64 global_id = 1;
+
+  // Time range for searching for navigations to delete. Client should delete
+  // all navigations to a URL between [start_time_usec, end_time_usec]
+  // if one of them matches a `global_id`.
+  optional int64 start_time_usec = 2;
+  optional int64 end_time_usec = 3;
+}
+
+message TimeRangeDirective {
+  // Both fields below must be filled in.  Otherwise, this delete directive
+  // must be ignored.
+
+  // The time on or after which entries must be deleted.
+  optional int64 start_time_usec = 1;
+  // The time on or before which entries must be deleted.
+  optional int64 end_time_usec = 2;
+
+  // Optional field to filter the entries with the matching app ID.
+  // This field is set only by Android which has app-specific history feature
+  // that allows users to generate/delete history entries from Custom Tabs on
+  // app, not from BrApp.
+  optional string app_id = 3;
+}
+
+message UrlDirective {
+  // Both fields below must be filled in.  Otherwise, this delete directive
+  // must be ignored.
+
+  // The URL that should be removed from history.
+  optional string url = 1;
+
+  // The time on or before which entries must be deleted.
+  // In microseconds since the Unix epoch.
+  optional int64 end_time_usec = 2;
+
+  // Optional field to filter the entries with the matching app ID.
+  // This field is set only by Android which has app-specific history feature
+  // that allows users to generate/delete history entries from Custom Tabs on
+  // app, not from BrApp.
+  optional string app_id = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/history_specifics.proto b/pyhindsight/lib/components/sync/protocol/history_specifics.proto
new file mode 100644
index 0000000..7b90a7a
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/history_specifics.proto
@@ -0,0 +1,152 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for history entries.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/sync_enums.proto";
+
+// A history sync entity - this roughly represents one navigation, including its
+// full redirect chain (but not referrals). Fields correspond to similarly named
+// fields in history::VisitRow and history::URLRow.
+message HistorySpecifics {
+  // Timestamp, also called "global ID" in some places (e.g. in delete
+  // directives). This uniquely identifies the entity.
+  optional int64 visit_time_windows_epoch_micros = 1;
+
+  // Cache GUID of the client that produced this entity, aka the "originator".
+  optional string originator_cache_guid = 2;
+
+  message RedirectEntry {
+    // ID of the visit on the originator client, unique within that client.
+    optional int64 originator_visit_id = 1;
+    // URL that was visited.
+    optional string url = 2;
+    // Title of the page corresponding to this URL.
+    optional string title = 3;
+    // True if the URL should NOT be used for auto-complete.
+    optional bool hidden = 4;
+    // The redirect type (if any).
+    optional SyncEnums.PageTransitionRedirectType redirect_type = 5;
+  }
+  // The redirect chain. The first entry is the URL the user originally
+  // navigated to; the last one is where they ended up. If there were no
+  // redirects, this has only one entry.
+  repeated RedirectEntry redirect_entries = 3;
+
+  // Whether the redirect chain in this entity is the continuation of a prior
+  // chain, and whether a continuation of this chain exists, in other entities.
+  // These are effectively the inverse of the CHAIN_START/CHAIN_END page
+  // transition qualifiers in Chrome. They are typically both false, since the
+  // whole chain is included in `redirect_entries`, but in some cases (notably,
+  // client redirects) a redirect chain may be split up across multiple
+  // entities.
+  optional bool redirect_chain_start_incomplete = 19;
+  optional bool redirect_chain_end_incomplete = 20;
+
+  // If this is set to true, then the redirect chain was too long and some
+  // entries were trimmed from the middle, so `redirect_entries` only
+  // corresponds to some of the first plus some of the last entries of the
+  // actual redirect chain.
+  optional bool redirect_chain_middle_trimmed = 21;
+
+  message PageTransition {
+    // The core transition type.
+    optional SyncEnums.PageTransition core_transition = 1 [default = LINK];
+    // Qualifiers:
+    // A supervised user tried to access this URL but was blocked.
+    optional bool blocked = 2;
+    // User used the Forward or Back button to navigate among browsing history.
+    optional bool forward_back = 3;
+    // User used the address bar to trigger this navigation.
+    optional bool from_address_bar = 4;
+    // User is navigating to the home page.
+    optional bool home_page = 5;
+  }
+  // The PageTransition for the navigation.
+  optional PageTransition page_transition = 4;
+
+  // The ID of the visit, on the originator client, that was a referrer for
+  // this one, or 0 if no referrer exists.
+  optional int64 originator_referring_visit_id = 5;
+  // The ID of the visit, on the originator client, that opened this one, or 0
+  // if no opener exists.
+  optional int64 originator_opener_visit_id = 6;
+  // The ID of the cluster that this visit belongs to on the originator client,
+  // or 0 if the originator client does not support setting this field or the
+  // visit does not belong to any cluster.
+  optional int64 originator_cluster_id = 22;
+
+  // The duration of the visit, in microseconds. Zero if the visit hasn't been
+  // finished (or the duration wasn't updated for some other reason).
+  optional int64 visit_duration_micros = 7;
+
+  // The kind of browser where this visit happened.
+  optional SyncEnums.BrowserType browser_type = 8;
+
+  // The SessionID of the window and tab where the visit happened. Can be used
+  // to link together possibly-related visits.
+  // Note: These are only unique per-client, so always use together with
+  // `originator_cache_guid`.
+  optional int32 window_id = 9;
+  optional int32 tab_id = 10;
+
+  // The ID for the task associated with this navigation, which is globally
+  // unique with high probability.
+  optional int64 task_id = 11;
+  // The IDs of ancestor tasks. These can be used to construct a tree of related
+  // visits.
+  optional int64 root_task_id = 12;
+  optional int64 parent_task_id = 13;
+
+  // The HTTP response code of the navigation.
+  optional int32 http_response_code = 14;
+
+  // The language of the content on the page, as an ISO 639 language code
+  // (usually two letters). May be "und" if the language couldn't be determined.
+  optional string page_language = 15;
+
+  // Whether a password field was found on the page.
+  optional SyncEnums.PasswordState password_state = 16;
+
+  // URL of the favicon for this page.
+  optional string favicon_url = 17;
+
+  // The URL of the referrer (indicated by `originator_referring_visit_id`), if
+  // any.
+  optional string referrer_url = 18;
+
+  // Visit has an image derived from public version of the page. This can be
+  // used to provide more visual experience.
+  optional bool has_url_keyed_image = 23;
+
+  message Category {
+    // ID of the category, this typically is an MID.
+    optional string id = 1;
+    // Weight of the category, this is an integer value informing the confidence
+    // of a visit belonging to this category.
+    optional int32 weight = 2;
+  }
+
+  // Categories tagged for the visit.
+  repeated Category categories = 24;
+
+  // Related search URLs for a Google SRP visit, to provide next steps to user.
+  repeated string related_searches = 25;
+
+  // ID of the app (non-BrApp) this entity was generated for, if any. Only
+  // visits originating from Android devices may have this set.
+  optional string app_id = 26;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/history_status.proto b/pyhindsight/lib/components/sync/protocol/history_status.proto
new file mode 100644
index 0000000..a9a4707
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/history_status.proto
@@ -0,0 +1,23 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message HistoryStatusRequest {}
+
+// Response to a history status request.
+message HistoryStatusResponse {
+  // Minimal time to wait before issuing another request.
+  optional int32 min_poll_interval_seconds = 1 [default = 3600];
+
+  // Indicates whether the history corpuses have any derived data for a user.
+  optional bool has_derived_data = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/loopback_server.proto b/pyhindsight/lib/components/sync/protocol/loopback_server.proto
new file mode 100644
index 0000000..27478cb
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/loopback_server.proto
@@ -0,0 +1,48 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol for persisting the loopback server state to disk.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/sync_entity.proto";
+
+// Serialization of the LoopbackServerEntity and its ancestors.
+message LoopbackServerEntity {
+  // Entity type mapping to one of the subclasses of LoopbackServerEntity.
+  enum Type {
+    UNKNOWN = 0;
+    BOOKMARK = 1;
+    PERMANENT = 2;
+    TOMBSTONE = 3;
+    UNIQUE = 4;
+  }
+
+  optional Type type = 1;
+  optional SyncEntity entity = 2;
+  optional int64 data_type = 3;
+}
+
+// Contains the loopback server state.
+message LoopbackServerProto {
+  // The protocol buffer format version.
+  optional int64 version = 1;
+
+  optional int64 store_birthday = 2;
+
+  repeated LoopbackServerEntity entities = 3;
+
+  // All Keystore keys known to the server.
+  repeated bytes keystore_keys = 4;
+
+  // The last entity ID that was assigned to an entity.
+  optional int64 last_version_assigned = 5;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/managed_user_setting_specifics.proto b/pyhindsight/lib/components/sync/protocol/managed_user_setting_specifics.proto
new file mode 100644
index 0000000..0a83dde
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/managed_user_setting_specifics.proto
@@ -0,0 +1,23 @@
+// Copyright 2013 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for managed user settings.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of managed user setting sync objects.
+message ManagedUserSettingSpecifics {
+  optional string name = 1;
+  optional string value = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/managed_user_shared_setting_specifics.proto b/pyhindsight/lib/components/sync/protocol/managed_user_shared_setting_specifics.proto
new file mode 100644
index 0000000..56a6b06
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/managed_user_shared_setting_specifics.proto
@@ -0,0 +1,31 @@
+// Copyright 2013 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for managed user shared settings.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of managed user shared setting sync objects.
+message ManagedUserSharedSettingSpecifics {
+  // The MU ID for the managed user to whom the setting applies.
+  optional string mu_id = 1;
+  // The key of the setting.
+  optional string key = 2;
+  // The setting value. The setting is a JSON encoding of an arbitrary
+  // Javascript value.
+  optional string value = 3;
+  // This flag is set by the server to acknowledge that it has committed a
+  // change to a setting.
+  optional bool acknowledged = 4 [default = false];
+}
diff --git a/pyhindsight/lib/components/sync/protocol/nigori_local_data.proto b/pyhindsight/lib/components/sync/protocol/nigori_local_data.proto
new file mode 100644
index 0000000..ad6037d
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/nigori_local_data.proto
@@ -0,0 +1,131 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/data_type_state.proto";
+import "components/sync/protocol/encryption.proto";
+import "components/sync/protocol/entity_metadata.proto";
+import "components/sync/protocol/nigori_specifics.proto";
+
+message CrossUserSharingKeys {
+  // Asymmetric private-keys used for cross user sharing.
+  repeated CrossUserSharingPrivateKey private_key = 1;
+}
+
+message LocalNigoriKeyBag {
+  // Used for encrypting within the sync account boundary.
+  repeated NigoriKey key = 2;
+}
+
+message CryptographerData {
+  // Contains all known Nigori keys.
+  optional LocalNigoriKeyBag key_bag = 1;
+
+  // Default key is the key, that should be used for encryption. Can be empty
+  // in case we have pending keys (waiting for explicit passphrase, or client
+  // didn't received keystore keys).
+  optional string default_key_name = 2;
+
+  // Contains cross user sharing related keys.
+  optional CrossUserSharingKeys cross_user_sharing_keys = 3;
+}
+
+message CustomPassphraseKeyDerivationParams {
+  // Method used for deriving keys from custom passphrase.
+  optional NigoriSpecifics.KeyDerivationMethod
+      custom_passphrase_key_derivation_method = 1;
+
+  // Salt used for the derivation of the key from the custom passphrase. Should
+  // be set iff custom_passphrase_key_derivation_method == SCRYPT_8192_8_11.
+  optional string custom_passphrase_key_derivation_salt = 2;
+}
+
+message NigoriModel {
+  // Represents state of the cryptographer.
+  optional CryptographerData cryptographer_data = 1;
+
+  // Contains the name of the key, used for encryption of
+  // NigoriSpecifics.keystore_decryptor_token, should always be the name of the
+  // latest keystore key. Equals to cryptographer_data.default_key_name iff it
+  // is Nigori in full keystore mode (not in backward compatible keystore
+  // mode).
+  optional string current_keystore_key_name = 2;
+
+  // Contains keybag in encrypted form, should be empty once we were able to
+  // decrypt keybag from specifics.
+  optional EncryptedData pending_keys = 3;
+
+  // PassphraseType used for encryption. IMPLICIT_PASSPRHASE shouldn't be used
+  // here.
+  optional NigoriSpecifics.PassphraseType passphrase_type = 4
+      [default = UNKNOWN];
+
+  // The time (in UNIX epoch milliseconds) at which the keystore migration was
+  // performed.
+  optional int64 keystore_migration_time = 5;
+
+  // The time (in UNIX epoch milliseconds) at which a custom passphrase was
+  // set.
+  // Note: this field may not be set if the custom passphrase was applied before
+  // corresponding field in NigoriSpecifics was introduced.
+  optional int64 custom_passphrase_time = 6;
+
+  // Params used for deriving keys from custom passphrase. Should be set iff
+  // `passphrase_type` is CUSTOM_PASSPHRASE.
+  optional CustomPassphraseKeyDerivationParams
+      custom_passphrase_key_derivation_params = 7;
+
+  // Indicates whether we need to encrypt all encryptable user types.
+  optional bool encrypt_everything = 8;
+
+  // The list of encrypted UserEncryptableTypes, represented by their specifics
+  // field number.
+  repeated int32 encrypted_types_specifics_field_number = 9;
+
+  // Keystore keys are used to decrypt keystore-based Nigori. Should be
+  // persisted in order to not ask the keystore server for them during every
+  // browser startup. Due to backward compatibility requirements keys are
+  // always Base64 encoded.
+  repeated string keystore_key = 10;
+
+  // Encryptor keystore decryptor token. Used for decryption of keystore Nigori
+  // in case keystore keys arrived after NigoriSpecifics.
+  optional EncryptedData pending_keystore_decryptor_token = 11;
+
+  // Contains the name of the latest available trusted vault key that was used
+  // as the default encryption key. Resets when the client go out of pending
+  // decryption state and transits to other passphrase types.
+  optional string last_default_trusted_vault_key_name = 12;
+
+  // Some debug-only fields for passphrase type TRUSTED_VAULT_PASSPHRASE.
+  optional NigoriSpecifics.TrustedVaultDebugInfo trusted_vault_debug_info = 13;
+
+  // Current Public-key.
+  optional CrossUserSharingPublicKey cross_user_sharing_public_key = 14;
+}
+
+// Sync proto to store Nigori data in storage. Proto should be encrypted with
+// os_crypt before storing it somewhere, because it contains sensitive data (
+// nigori_model.cryptographer_data.key_bag and nigori_model.keystore_keys).
+message NigoriLocalData {
+  // Global metadata.
+  optional DataTypeState data_type_state = 1;
+
+  // Metadata for Nigori entity.
+  optional EntityMetadata entity_metadata = 2;
+
+  // Nigori model state.
+  optional NigoriModel nigori_model = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/nigori_specifics.proto b/pyhindsight/lib/components/sync/protocol/nigori_specifics.proto
new file mode 100644
index 0000000..59e1a4d
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/nigori_specifics.proto
@@ -0,0 +1,300 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for nigori keys.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/encryption.proto";
+
+message NigoriKey {
+  // Note that M78 and before rely on the name being populated, at least for
+  // the main encrypted keybag within NigoriSpecifics.
+  optional string deprecated_name = 1 [deprecated = true];
+  optional bytes deprecated_user_key = 2 [deprecated = true];
+  optional bytes encryption_key = 3;
+  optional bytes mac_key = 4;
+}
+
+message CrossUserSharingPrivateKey {
+  // The key version, used for key rotation.
+  optional int32 version = 1;
+  // Private key on Curve25519 (32 bytes).
+  // Encryption: Hybrid Public Key Encryption (HPKE)
+  // KEM: DHKEM_X25519_HKDF_SHA256
+  // KDF: HKDF_SHA256
+  // AEAD: CHACHA20_POLY1305
+  optional bytes x25519_private_key = 2;
+}
+
+message CrossUserSharingPublicKey {
+  // The key version, used for key rotation and consensus.
+  optional int32 version = 1;
+  // Public key on Curve25519 (32 bytes).
+  // Encryption: Hybrid Public Key Encryption (HPKE)
+  // KEM: DHKEM_X25519_HKDF_SHA256
+  // KDF: HKDF_SHA256
+  // AEAD: CHACHA20_POLY1305
+  optional bytes x25519_public_key = 2;
+}
+
+message EncryptionKeys {
+  // Used for encrypting data in the user's account.
+  repeated NigoriKey key = 2;
+  // Used for encrypting/authenticating using Public-private cryptography
+  // primarily across user accounts, e.g. sharing invitations.
+  repeated CrossUserSharingPrivateKey cross_user_sharing_private_key = 3;
+}
+
+// Deprecated: use EncryptionKeys instead.
+message NigoriKeyBag {
+  option deprecated = true;
+
+  // Used for encrypting data in the user's account.
+  repeated NigoriKey key = 2;
+}
+
+// Information about the experiment group to auto-upgrade users to trusted vault
+// passphrase type.
+message TrustedVaultAutoUpgradeExperimentGroup {
+  // ID of cohort account belongs to. An integer within the range [1, 99].
+  optional int32 cohort = 1;
+
+  // Within each cohort, there are multiple experiment groups, and each group
+  // has an associated type.
+  enum Type {
+    TYPE_UNSPECIFIED = 0;
+    TREATMENT = 1;
+    CONTROL = 2;
+    VALIDATION = 3;
+  }
+
+  optional Type type = 2;
+
+  // For each cohort and group type, there may be zero, one or more groups.
+  // To support the case where two or more exists, the index below can be used.
+  // This is primarily intended for validation groups.
+  optional int32 type_index = 3;
+}
+
+// Properties of nigori sync object.
+message NigoriSpecifics {
+  // Encrypted proto of type EncryptionKeys.
+  optional EncryptedData encryption_keybag = 1;
+  // Once keystore migration is performed, we have to freeze the keybag so that
+  // older clients (that don't support keystore encryption) do not attempt to
+  // update the keybag.
+  // Previously `using_explicit_passphrase`.
+  optional bool keybag_is_frozen = 2;
+
+  // Obsolete encryption fields. These were deprecated due to legacy versions
+  // that understand their usage but did not perform encryption properly.
+  reserved 3;
+  reserved "deprecated_encrypt_bookmarks";
+  reserved 4;
+  reserved "deprecated_encrypt_preferences";
+  reserved 5;
+  reserved "deprecated_encrypt_autofill_profile";
+  reserved 6;
+  reserved "deprecated_encrypt_autofill";
+  reserved 7;
+  reserved "deprecated_encrypt_themes";
+  reserved 8;
+  reserved "deprecated_encrypt_typed_urls";
+  reserved 9;
+  reserved "deprecated_encrypt_extensions";
+  reserved 10;
+  reserved "deprecated_encrypt_sessions";
+  reserved 11;
+  reserved "deprecated_encrypt_apps";
+  reserved 12;
+  reserved "deprecated_encrypt_search_engines";
+  reserved 13;
+  reserved "encrypt_bookmarks";
+  reserved 14;
+  reserved "encrypt_preferences";
+  reserved 15;
+  reserved "encrypt_autofill_profile";
+  reserved 16;
+  reserved "encrypt_autofill";
+  reserved 17;
+  reserved "encrypt_themes";
+  reserved 18;
+  reserved "encrypt_typed_urls";
+  reserved 19;
+  reserved "encrypt_extensions";
+  reserved 20;
+  reserved "encrypt_sessions";
+  reserved 21;
+  reserved "encrypt_apps";
+  reserved 22;
+  reserved "encrypt_search_engines";
+
+  // Deprecated on clients where tab sync is enabled by default.
+  reserved 23;
+  reserved "sync_tabs";
+
+  // If true, all current and future datatypes will be encrypted.
+  optional bool encrypt_everything = 24;
+
+  // Obsolete encryption fields.
+  reserved 25;
+  reserved "encrypt_extension_settings";
+  reserved 26;
+  reserved "encrypt_app_notifications";
+  reserved 27;
+  reserved "encrypt_app_settings";
+
+  // User device information. Contains information about each device that has a
+  // sync-enabled Chrome browser connected to the user account.
+  // This has been moved to the DeviceInfo message.
+  reserved 28;
+  reserved "deprecated_device_information";
+
+  // Enable syncing favicons as part of tab sync.
+  optional bool sync_tab_favicons = 29;
+
+  // The state of the passphrase required to decrypt `encryption_keybag`.
+  enum PassphraseType {
+    // Proto enums should begin with an 'unknown' value for switch statements,
+    // unknown fields, etc.
+    UNKNOWN = 0;
+    // Gaia-based encryption passphrase. Legacy.
+    IMPLICIT_PASSPHRASE = 1;
+    // Keystore key encryption passphrase. Uses `keystore_bootstrap` to
+    // decrypt `encryption_keybag`.
+    KEYSTORE_PASSPHRASE = 2;
+    // Previous Gaia-based passphrase frozen and treated as a custom passphrase.
+    FROZEN_IMPLICIT_PASSPHRASE = 3;
+    // User provided custom passphrase.
+    CUSTOM_PASSPHRASE = 4;
+    // Encryption key provided by a trusted vault.
+    TRUSTED_VAULT_PASSPHRASE = 5;
+  }
+
+  // An `int` field is used instead of enum PassphraseType so we can better
+  // handle unknown values coming from later versions. Prior to M77, this was an
+  // enum so old clients will assume IMPLICIT_PASSPHRASE for values greater than
+  // 4.
+  optional int32 passphrase_type = 30 [default = 1];
+
+  // The keystore decryptor token blob. Encrypted with the keystore key, and
+  // contains the encryption key used to decrypt `encryption_keybag`.
+  // Only set if passphrase_state == KEYSTORE_PASSPHRASE.
+  optional EncryptedData keystore_decryptor_token = 31;
+
+  // The time (in milliseconds since Unix epoch) at which the keystore migration
+  // was performed.
+  optional int64 keystore_migration_time = 32;
+
+  // The time (in milliseconds since Unix epoch) at which a custom passphrase
+  // was set. Note: this field may not be set if the custom passphrase was
+  // applied before this field was introduced.
+  optional int64 custom_passphrase_time = 33;
+
+  // Obsolete encryption fields.
+  reserved 34;
+  reserved "encrypt_dictionary";
+  reserved 35;
+  reserved 36;
+  reserved 37;
+  reserved "encrypt_articles";
+  reserved 38;
+  reserved "encrypt_app_list";
+  reserved 39;
+  reserved "encrypt_autofill_wallet_metadata";
+
+  // Boolean indicating whether this node was originally missing a
+  // `keystore_migration_time` field value, and was fixed on the server by
+  // giving the field a value.
+  // THIS FIELD SHOULD ONLY BE SET BY THE SERVER.
+  optional bool server_only_was_missing_keystore_migration_time = 40;
+
+  // Obsolete encryption fields.
+  reserved 41;
+  reserved "encrypt_arc_package";
+  reserved 42;
+  reserved "encrypt_printers";
+  reserved 43;
+  reserved "encrypt_reading_list";
+  reserved 44;
+  reserved "encrypt_mountain_shares";
+
+  enum KeyDerivationMethod {
+    // This comes from a <= M69 client, who does not know about the field
+    // (but implicitly uses PBKDF2_HMAC_SHA1_1003).
+    UNSPECIFIED = 0;
+    // PBKDF2-HMAC-SHA1 with 1003 iterations and constant hardcoded salt. Was
+    // implicitly used in <= M69.
+    PBKDF2_HMAC_SHA1_1003 = 1;
+    // scrypt with N = 2^13, r = 8, p = 11 and random salt. Was added in M70.
+    SCRYPT_8192_8_11 = 2;
+  }
+
+  // ID of the method used to derive the encryption key from a custom
+  // passphrase. Should be set only when `passphrase_type` is CUSTOM_PASSPHRASE
+  // and only based on CustomPassphraseKeyDerivationMethod. This field has been
+  // added in M70. All previous versions just ignore it, attempt to use
+  // PBKDF2_HMAC_SHA1_1003 and, thus, reject any passphrase if a different
+  // method has been used. The default corresponds to UNSPECIFIED. An `int`
+  // field is used so we can detect unknown values coming from later versions.
+  optional int32 custom_passphrase_key_derivation_method = 45 [default = 0];
+
+  // Base64-encoded salt used for the derivation of the key from the custom
+  // passphrase. Valid only if custom_passphrase_key_derivation_method ==
+  // SCRYPT_8192_8_11, ignored in other cases.
+  optional string custom_passphrase_key_derivation_salt = 46;
+
+  // Obsolete encryption fields.
+  reserved 47;
+  reserved "encrypt_send_tab_to_self";
+  reserved 48;
+  reserved "encrypt_web_apps";
+  reserved 49;
+  reserved "encrypt_os_preferences";
+
+  // Some debug-only fields for passphrase type TRUSTED_VAULT_PASSPHRASE.
+  message TrustedVaultDebugInfo {
+    // The time (in milliseconds since Unix epoch) at which the trusted vault
+    // migration was performed.
+    optional int64 migration_time = 1;
+
+    // The version (aka key epoch) corresponding to the Nigori keybag.
+    optional int32 key_version = 2;
+
+    reserved 3, 4;
+
+    // Experiment group assignment (if any) related to auto-upgrading users into
+    // trusted vault passphrase.
+    optional TrustedVaultAutoUpgradeExperimentGroup
+        auto_upgrade_experiment_group = 5;
+
+    // The time (in milliseconds since Unix epoch) last update of the auto
+    // upgrade experiment group was made.
+    optional int64
+        auto_upgrade_experiment_group_modification_time_unix_epoch_millis = 6;
+  }
+
+  optional TrustedVaultDebugInfo trusted_vault_debug_info = 50;
+
+  // Obsolete encryption fields.
+  reserved 51;
+  reserved "encrypt_workspace_desk";
+  reserved 52;
+  reserved "encrypt_printers_authorization_servers";
+
+  // Current cross user sharing Public-key to expose in server registry
+  // for sharing offers outside account boundary.
+  optional CrossUserSharingPublicKey cross_user_sharing_public_key = 53;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/note_entity.proto b/pyhindsight/lib/components/sync/protocol/note_entity.proto
new file mode 100644
index 0000000..ccadc03
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/note_entity.proto
@@ -0,0 +1,36 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message NoteEntity {
+  enum TargetType {
+    TARGET_TYPE_UNSPECIFIED = 0;
+
+    // Page target type makes the note global to the page. It does not associate
+    // with any user selection.
+    TARGET_TYPE_PAGE = 1;
+  }
+
+  // Plain text of the note.
+  optional string plain_text = 1;
+
+  // Rich text of the note. It will be used when plain_text is empty and the UI
+  // supports rich text.
+  optional string rich_text = 2;
+
+  // The type of the note target. Currently only PAGE target type is supported.
+  /* required */ optional TargetType target_type = 3;
+
+  // The current version of the note. If this version is newer than the note
+  // version of the browser the note won't be displayed.
+  /* required */ optional int32 current_note_version = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/os_preference_specifics.proto b/pyhindsight/lib/components/sync/protocol/os_preference_specifics.proto
new file mode 100644
index 0000000..53db333
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/os_preference_specifics.proto
@@ -0,0 +1,26 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for Chrome OS preferences.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/preference_specifics.proto";
+
+// Properties of a synced Chrome OS system preference. Uses PreferenceSpecifics
+// instead of declaring name and value fields to allow more code sharing in the
+// client (e.g. all PrefModelAssociators can operate on PreferenceSpecifics).
+message OsPreferenceSpecifics {
+  optional PreferenceSpecifics preference = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/os_priority_preference_specifics.proto b/pyhindsight/lib/components/sync/protocol/os_priority_preference_specifics.proto
new file mode 100644
index 0000000..58b38c1
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/os_priority_preference_specifics.proto
@@ -0,0 +1,26 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for Chrome OS priority preferences.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/preference_specifics.proto";
+
+// Properties of a Chrome OS priority preference. Uses PreferenceSpecifics
+// instead of declaring name and value fields to allow more code sharing
+// in the client (e.g. all PrefModelAssociators can use PreferenceSpecifics).
+message OsPriorityPreferenceSpecifics {
+  optional PreferenceSpecifics preference = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/password_sharing_invitation_specifics.proto b/pyhindsight/lib/components/sync/protocol/password_sharing_invitation_specifics.proto
new file mode 100644
index 0000000..2d43921
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/password_sharing_invitation_specifics.proto
@@ -0,0 +1,134 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/nigori_specifics.proto";
+
+message PasswordSharingInvitationData {
+  // Contains password fields required for sending. See PasswordSpecificsData
+  // for field descriptions.
+  message PasswordGroupElementData {
+    // See PasswordSpecificsData::Scheme for values.
+    optional int32 scheme = 2;
+    optional string signon_realm = 3;
+    optional string origin = 4;
+    optional string username_element = 5;
+    optional string password_element = 7;
+    optional string display_name = 8;
+    optional string avatar_url = 9;
+  }
+
+  message PasswordGroupData {
+    optional string username_value = 1;
+    optional string password_value = 2;
+    repeated PasswordGroupElementData element_data = 3;
+  }
+
+  reserved 1;
+
+  optional PasswordGroupData password_group_data = 2;
+}
+
+// Contains user profile information.
+message UserDisplayInfo {
+  // Primary email address of the user.
+  optional string email = 1;
+
+  // The user's full name.
+  optional string display_name = 2;
+
+  // Portrait photo of the user.
+  optional string profile_image_url = 3;
+}
+
+message UserInfo {
+  // Obfuscated Gaia ID.
+  optional string user_id = 1;
+
+  optional UserDisplayInfo user_display_info = 2;
+
+  // Latest user's public key registered on the server.
+  optional CrossUserSharingPublicKey cross_user_sharing_public_key = 3;
+}
+
+// Incoming invitations for password sending.
+message IncomingPasswordSharingInvitationSpecifics {
+  // Unique client tag for the invitation. This does *not* have to be the same
+  // GUID as for the outgoing invitation.
+  optional string guid = 1;
+
+  // Profile information about the sender of the password. Sender's public key
+  // is used to authenticate the sender for `encrypted_key_for_recipient`.
+  optional UserInfo sender_info = 2;
+
+  // Encrypted PasswordSharingInvitationData using recipient's public key
+  // corresponding to `recipient_key_version` and sender's private key to
+  // authenticate the sender, see https://www.rfc-editor.org/rfc/rfc9180.html.
+  optional bytes encrypted_password_sharing_invitation_data = 3;
+
+  // An unsynced field for use internally on the client. This field should
+  // never be set in any network-based communications because it contains
+  // unencrypted material.
+  optional PasswordSharingInvitationData client_only_unencrypted_data = 4;
+
+  optional uint32 recipient_key_version = 6;
+
+  reserved 5;
+}
+
+// Outgoing invitations for password sending.
+message OutgoingPasswordSharingInvitationSpecifics {
+  // Unique client tag for the invitation, generated by the client.
+  optional string guid = 1;
+
+  // Recipient's user identifier (obfuscated Gaia ID).
+  optional string recipient_user_id = 2;
+
+  // Encrypted PasswordSharingInvitationData using recipient's public key
+  // corresponding to `recipient_key_version` and sender's private key to
+  // authenticate the sender, see https://www.rfc-editor.org/rfc/rfc9180.html.
+  optional bytes encrypted_password_sharing_invitation_data = 3;
+
+  // An unsynced field for use internally on the client. This field should
+  // never be set in any network-based communications because it contains
+  // unencrypted material.
+  optional PasswordSharingInvitationData client_only_unencrypted_data = 4;
+
+  optional uint32 recipient_key_version = 6;
+
+  // Version of Public key of the sender which is used to authenticate the
+  // sender of the password. Must be equal to the latest committed version.
+  optional uint32 sender_key_version = 7;
+
+  reserved 5;
+}
+
+// Used for the server to return fine-grained commit errors back to the client.
+message OutgoingPasswordSharingInvitationCommitError {
+  // This enum is used in histograms. Entries should not be renumbered and
+  // numeric values should never be reused. Also remember to update in
+  // tools/metrics/histograms/enums.xml.
+  // LINT.IfChange(OutgoingPasswordSharingInvitationCommitError)
+  enum ErrorCode {
+    UNKNOWN = 0;
+
+    // Sender's public key version is different on the server.
+    PUBLIC_KEY_VERSION_MISMATCH = 1;
+
+    // The sender and the recipient are not in the same family according to the
+    // Google family service.
+    NOT_FAMILY_MEMBER = 2;
+  }
+  // LINT.ThenChange(/tools/metrics/histograms/metadata/sync/enums.xml:OutgoingPasswordSharingInvitationCommitError)
+
+  optional ErrorCode error_code = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/password_sharing_recipients.proto b/pyhindsight/lib/components/sync/protocol/password_sharing_recipients.proto
new file mode 100644
index 0000000..21a9268
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/password_sharing_recipients.proto
@@ -0,0 +1,39 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/password_sharing_invitation_specifics.proto";
+
+// A message to obtain a list of recipients for sending a password.
+message PasswordSharingRecipientsRequest {
+  // The request returns family members for the user and that is why no
+  // additional fields are required.
+}
+
+message PasswordSharingRecipientsResponse {
+  enum PasswordSharingRecipientsResult {
+    UNKNOWN = 0;
+
+    // The user is a member of a family and the request succeeded.
+    SUCCESS = 1;
+
+    // Not a family member, used to distinguish from a family with
+    // only one member.
+    NOT_FAMILY_MEMBER = 2;
+  }
+  optional PasswordSharingRecipientsResult result = 1;
+
+  // List of possible recipients for sending a password. Note that public key
+  // may be absent if a recipient can’t receive a password (e.g. due to an older
+  // Chrome version).
+  repeated UserInfo recipients = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/password_specifics.proto b/pyhindsight/lib/components/sync/protocol/password_specifics.proto
new file mode 100644
index 0000000..9e6d006
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/password_specifics.proto
@@ -0,0 +1,369 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for password data.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/encryption.proto";
+
+// These are the properties that get serialized into the `encrypted` field of
+// PasswordSpecifics. They correspond to fields in
+// password_manager::PasswordForm.
+//
+// Sync unique tag is calculated as
+// EscapePath(origin) + "|" +
+// EscapePath(username_element) + "|" +
+// EscapePath(username_value) + "|" +
+// EscapePath(password_element) + "|" +
+// EscapePath(signon_realm)
+// where '+' is the string concatenation operation. EscapePath escapes a partial
+// or complete file/pathname. This includes non-printable, non-7bit, and
+// (including space) the following characters ' "#%:<>?[\]^`{|}'. The space
+// character is encoded as '%20'.
+
+// A simple example of PasswordSpecificsData, as created by Chrome for a web
+// form that the user submitted. E.g. federated credentials or credentials for
+// Android apps may have different fields set.
+// PasswordSpecificsData {
+//   action: "https://example.com/",
+//   avatar_url: "",
+//   blacklisted: false,
+//   date_created: 13305119271948046,
+//   date_last_used: 13305119270102691,
+//   date_password_modified_windows_epoch_micros: 13305119271949070,
+//   display_name: "",
+//   federation_url: "",
+//   notes: {},
+//   origin: "https://rsolomakhin.github.io/autofill/",
+//   password_element: "password",
+//   password_issues: {},
+//   password_value: "pwd",
+//   scheme: 0,
+//   signon_realm: "https://rsolomakhin.github.io/",
+//   times_used: 0,
+//   type: 0,
+//   username_element: "username",
+//   username_value: "Superman"
+// }
+
+// All the strings are encoded with UTF-8. URLs are encoded in Punycode.
+message PasswordIssues {
+  message PasswordIssue {
+    // Timestamp set by a client detecting the issue for the first time.
+    // Number of microseconds since Windows epoch (1601).
+    // This can be unset even if is_muted is set in a few cases in
+    // storage (for a time mutes were written without setting this
+    // field - fixed starting 2021-11-10).
+    optional uint64 date_first_detection_windows_epoch_micros = 1;
+
+    // Whether the issue was muted by user.
+    optional bool is_muted = 2;
+
+    // Whether the backend should notify the user about this issue.
+    // Set to true if the user hasn't already seen a client notification for
+    // this issue (e.g. a leak detection prompt in Chrome). The backend sending
+    // notifications does not reset this field. All other sources can write this
+    // in both `PasswordSpecificsData` and `PasswordSpecificsMetadata` and do
+    // so.
+    optional bool trigger_notification_from_backend_on_detection = 3;
+  }
+  optional PasswordIssue leaked_password_issue = 1;
+  optional PasswordIssue reused_password_issue = 2;
+  optional PasswordIssue weak_password_issue = 3;
+  optional PasswordIssue phished_password_issue = 4;
+}
+
+message PasswordSpecificsData {
+    // The different types of the saved credential.
+  enum Scheme {
+    // SCHEME_HTML, the credential represents either a parsed HTML form, or an
+    // android credential or a password saved through Credential Management API
+    // (https://w3c.github.io/webappsec/specs/credentialmanagement/).
+    SCHEME_HTML = 0;
+    // SCHEME_BASIC, basic access http authentication.
+    SCHEME_BASIC = 1;
+    // SCHEME_DIGEST, digest access authentication.
+    SCHEME_DIGEST = 2;
+    // SCHEME_OTHER, another proxy access authentication.
+    SCHEME_OTHER = 3;
+    // USERNAME_ONLY, partial credentials saved on Android that contain only
+    // username and miss the password.
+    USERNAME_ONLY = 4;
+  }
+  // See the enum above.
+  optional int32 scheme = 1;
+
+  // Signon realm stores information on where the saved password was stored, and
+  // where it's supposed to be filled again.
+  //
+  // It can take various formats depending on the exact circumstances where it
+  // was recorded. Note that the format is *not* guaranteed to be a valid URL or
+  // URI:
+  //
+  //  * For parsed web forms and normal passwords saved through Credential
+  //  Manager
+  //    API: <http-scheme>://<url-host>[:<url-port>]/
+  //
+  //    where
+  //      <http-scheme> is one of "http" or "https"
+  //      <url-host> is the host for which the password was stored
+  //      <url-port> is the option port on the host
+  //    The signon realm is a valid URL in this case with an empty path.
+  //    Examples:
+  //      http://www.example.com/
+  //      https://127.0.0.1/
+  //      http://www.google.com:8080/
+  //      http://192.168.1.254/
+  //      https://accounts.google.com/
+  //
+  //  * For Android apps saved through Autofill with Google:
+  //      android://<hash-of-cert>@<package-name>/
+  //    where
+  //      <hash-of-cert> is the base64 encoded SHA512 of the app's public
+  //      certificate <package-name> is the app's package name
+  //    Examples:
+  //      android://kCyQDzpaoAX2gs-1zdGPKNAeICb8LzRFOxa4NCq0jO8c8d_NFS_q-Y35bU3Nq3GmFV2lLurmNvIZa6YPYZwmWg==@com.pinterest/
+  //      android://mNUCvTnoWBkzIhSSkVj-uzAdK42YagmCmyUtPoC6JPmYAN3wKpmTdIRsdJtz6pzNBye8XL7nBbEcx-y9CJeo9A==@com.twitter.android.lite/
+  //
+  //  * For federated credentials:
+  //      federation://<origin_host>/<federation_host>
+  //    where
+  //      <origin_host> is the host for which the login information was stored
+  //      <federation_host> is the host of the federation provider that was
+  //        used to sign in
+  //    Examples:
+  //      federation://www.example.com/accounts.google.com
+  //      federation://uk.trustpilot.com/www.facebook.com
+  //
+  //  * For proxy auth:
+  //      <proxy-host>[:<proxy_port>]/<auth-realm>
+  //    where
+  //      <proxy-host> is the host of the proxy for which the password was
+  //      stored
+  //      <proxy-port> is the port of the proxy
+  //      <auth-realm> is a string provided by the proxy during authentication.
+  //      It can contain spaces.
+  //    Examples:
+  //      proxy2.eq.edu.au:80/MISldap
+  //      proxy.det.nsw.edu.au:8080/NSW Department of Education
+  //      10.47.2.250:3128/Squid Proxy Server CPUT
+  //      default.go2https.com:443/(******Get password from vpnso.com/account/
+  //      *****)
+  //
+  //  * For HTTP basic auth:
+  //      <http-scheme>://<url-host>[:<url-port>]/<auth-realm>
+  //    where
+  //      <http-scheme> is one of "http" or "https"
+  //      <url-host> is the host for which the password was stored
+  //      <url-port> is the option port on the host
+  //      <auth-realm> is a string provided by the host during authentication.
+  //      It can contain spaces.
+  //    Examples:
+  //      http://192.168.1.1/Broadband Router
+  //      http://192.168.0.1/TP-LINK Wireless N Router WR841N
+  //      http://192.168.1.1/index.htm
+  //      https://www.edge.asic.gov.au/ASIC eBusiness
+  optional string signon_realm = 2;
+
+  // For parsed web forms and Credential Management API:
+  //     url-scheme://url-host[:url-port]/path
+  // For Android: "android://<hash of cert>@<package name>/"
+  // For proxy/HTTP auth: url-scheme://url-host[:url-port]/path
+  optional string origin = 3;
+
+  // Only for web-parsed forms - the action target of the form:
+  //     url-scheme://url-host[:url-port]/path
+  optional string action = 4;
+
+  // Only for web-parsed forms - the name of the element containing username.
+  optional string username_element = 5;
+
+  // For all: the username.
+  // For blacklisted forms: <empty>.
+  optional string username_value = 6;
+
+  // Only for web-parsed forms - the name of the element containing password.
+  optional string password_element = 7;
+
+  // For all: the password.
+  // For federated logins and blacklisted forms: <empty>
+  optional string password_value = 8;
+
+  // Deprecated: http://crbug.com/413020
+  // True if the credential was saved for a HTTPS session with a valid SSL cert.
+  // Ignored for Android apps.
+  optional bool ssl_valid = 9 [deprecated = true];
+
+  // True for the last credential used for logging in on a given site.
+  // Deprecated in M81.
+  optional bool preferred = 10 [deprecated = true];
+
+  // Time when the credential was created. Amount of microseconds since 1601.
+  optional int64 date_created = 11;
+
+  // True, if user chose permanently not to save the credentials for the form.
+  optional bool blacklisted = 12;
+
+  // kFormSubmission(0), user manually filled the username and the password
+  // in the form.
+  // kGenerated(1), the credential was auto generated.
+  // kApi(2), the credential was generated from Credential Management API.
+  // kManuallyAdded(3), user manually created the password credential
+  // via Settings.
+  // kImported(4), the credential was imported using the import flow.
+  // kReceivedViaSharing(5), the credential has been received via the password
+  // sharing feature.
+  optional int32 type = 13;
+
+  // Number of times this login was used for logging in using an HTML form.
+  // Chrome uses this field to distinguish log-in and sign-up forms.
+  optional int32 times_used = 14;
+
+  // A human readable name of the account holder. Set by CredentialManager API
+  // and Android.
+  optional string display_name = 15;
+
+  // A URL of the avatar for the credential. Set by CredentialManager API and
+  // Android.
+  optional string avatar_url = 16;
+
+  // A URL of the IdP used to verify the credential. Set by Credential Manager
+  // API and Android.
+  optional string federation_url = 17;
+
+  // Time when the credential was last used. This covers *successful* logins to
+  // the website, and explicit updates to the password. It does *not* cover if
+  // the password just gets filled but not actually submitted, or if the login
+  // failed (see `date_last_filled_windows_epoch_micros` for that).
+  // Note that password consumers other than Chrome (e.g. Google Play Services)
+  // might not update this at all.
+  // Amount of microseconds since 1601, aka Windows epoch.
+  optional int64 date_last_used = 18;
+
+  // Set if an issue was detected that puts this password at risk. All the
+  // clients are expected to clear the field when the password value is updated.
+  // 'reused' part can be additionally reset when the analysis on the entire
+  // password store is completed.
+  optional PasswordIssues password_issues = 19;
+
+  // Time when the `password_value` was last modified. For new credentials it
+  // should be set to `date_created`. For subsequent updates the timestamp is
+  // changed if and only if the new password value was saved.
+  // Number of microseconds since Windows epoch (1601).
+  optional int64 date_password_modified_windows_epoch_micros = 20;
+
+  message Notes {
+    message Note {
+      // The display name must be unique within the scope of a password.
+      optional string unique_display_name = 1;
+      // The user-defined value of the note.
+      optional string value = 2;
+      // The creation time of the note. Number of microseconds since 1601.
+      optional int64 date_created_windows_epoch_micros = 3;
+      // Whether the value of the note is not displayed in plain text by
+      // default.
+      optional bool hide_by_default = 4;
+    }
+    repeated Note note = 1;
+  }
+  reserved 21;
+  // Set of extra notes that the user attached to the password. The presence of
+  // this field, even with an empty Notes message, becomes the authoritative
+  // value for notes and would disregard whatever `encrypted_notes_backup`
+  // contains.
+  optional Notes notes = 22;
+
+  // For credentials that have been shared by another user, this field captures
+  // the sender email. It's empty for credentials that weren't received via
+  // password sharing feature.
+  optional string sender_email = 23;
+
+  // Similar to `sender_email` but for the sender name.
+  optional string sender_name = 24;
+
+  // The timestamp when the password was received via sharing feature from
+  // another user.
+  optional int64 date_received_windows_epoch_micros = 25;
+
+  // Whether the user has been already notified that they received this password
+  // from another user via the password sharing feature. This is synced to avoid
+  // showing the notification on multiple devices.
+  optional bool sharing_notification_displayed = 26;
+
+  // Similar to `sender_email` but for the url of the sender profile image.
+  optional string sender_profile_image_url = 27;
+
+  // Similar to `date_last_used` but covers when the password was last *filled*
+  // into a form (through autofill or other UI surfaces).
+  optional int64 date_last_filled_windows_epoch_micros = 28;
+}
+
+// Contains the password specifics metadata which simplifies its lookup.
+message PasswordSpecificsMetadata {
+  // The signon realm for the credential. For more details, see the
+  // `signon_realm` field in PasswordSpecificsData.
+  optional string url = 1;
+
+  // True, if user chose permanently not to save the credentials for the form.
+  // Introduced in M82. Copy from PasswordSpecificsData.blacklisted.
+  optional bool blacklisted = 2;
+
+  // Copy from PasswordSpecificsData.date_last_used.
+  // Introduced in M112.
+  optional int64 date_last_used_windows_epoch_micros = 3;
+
+  // Copy from PasswordSpecificsData.password_issues. Introduced in M114.
+  optional PasswordIssues password_issues = 4;
+
+  // Copy from PasswordSpecificsData.type. Introduced in M119.
+  optional int32 type = 13;
+}
+
+// Properties of password sync objects.
+message PasswordSpecifics {
+  // The actual password data. Contains an encrypted PasswordSpecificsData
+  // message.
+  optional EncryptedData encrypted = 1;
+  // An unsynced field for use internally on the client. This field should
+  // never be set in any network-based communications because it contains
+  // unencrypted material.
+  optional PasswordSpecificsData client_only_encrypted_data = 2;
+  // Password related metadata, which is sent to the server side. The field
+  // should never be set for full encryption users. If encryption is enabled,
+  // this field must be cleared.
+  optional PasswordSpecificsMetadata unencrypted_metadata = 3;
+  reserved 4;
+  // An encrypted backup of the notes field inside the PasswordSpecificsData.
+  // The Sync server preserves the contents of this field across commits from
+  // legacy clients that don't set this field. It is the responsibility of Sync
+  // clients to populate the contents of PasswordSpecificsData notes fields
+  // using the contents of this field. This should be deprecated together with
+  // the logic for preserving it on the server when clients without support for
+  // the `notes` field are no longer allowed by the server (below support
+  // version horizon).
+  //
+  // Encryption key considerations:
+  // a) For commits, the client must use the same key for both encrypted blobs.
+  // b) For handling getupdates, the two keys may NOT necessarily match the
+  //    encryption key used, as in theory the new blob could be "behind" if key
+  //    rotation took place. As of today, it is safe to assume that if
+  //    `encrypted` is decryptable by a client, then `encrypted_notes_backup`
+  //    must be decryptable too (i.e. the Nigori keybag should include older
+  //    versions of the key). But not the other way round.
+  //
+  // If both `encrypted_notes_backup` and the `notes` in `encrypted` are
+  // populated, the one in notes is considered the authoritative value.
+  optional EncryptedData encrypted_notes_backup = 5;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/persisted_entity_data.proto b/pyhindsight/lib/components/sync/protocol/persisted_entity_data.proto
new file mode 100644
index 0000000..1a79925
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/persisted_entity_data.proto
@@ -0,0 +1,26 @@
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/entity_specifics.proto";
+
+// Sync proto to store entity data similar to what the legacy Directory used
+// to store, used to persist data locally and never sent through the wire.
+//
+// Because it's conceptually similar to SyncEntity (actual protocol) and it's
+// unclear how big this'll grow, we've kept compatibility with SyncEntity by
+// using the same field numbers.
+message PersistedEntityData {
+  // See corresponding fields in SyncEntity for details.
+  optional string name = 8;
+  optional EntitySpecifics specifics = 21;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/plus_address_setting_specifics.proto b/pyhindsight/lib/components/sync/protocol/plus_address_setting_specifics.proto
new file mode 100644
index 0000000..e19a847
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/plus_address_setting_specifics.proto
@@ -0,0 +1,27 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Used to sync settings for `PLUS_ADDRESS`. Since these settings originate from
+// the user's account, they are not reusing standard syncable prefs.
+message PlusAddressSettingSpecifics {
+  optional string name = 1;
+  // The value of the setting. Which variant is set depends on the setting.
+  oneof Value {
+    bool bool_value = 2;
+    string string_value = 3;
+    int64 int_value = 4;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/plus_address_specifics.proto b/pyhindsight/lib/components/sync/protocol/plus_address_specifics.proto
new file mode 100644
index 0000000..088dc61
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/plus_address_specifics.proto
@@ -0,0 +1,27 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message PlusAddressSpecifics {
+  // A stable, unique identifier, generated by the PlusAddress backend.
+  optional string profile_id = 1;
+  // The origin that the `plus_email` is generated for.
+  optional string facet = 2;
+  optional PlusEmail plus_email = 3;
+}
+
+message PlusEmail {
+  optional string email_address = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/power_bookmark_specifics.proto b/pyhindsight/lib/components/sync/protocol/power_bookmark_specifics.proto
new file mode 100644
index 0000000..ac892c3
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/power_bookmark_specifics.proto
@@ -0,0 +1,57 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/note_entity.proto";
+
+// Data structure dedicated to each power type.
+// Should keep the field numbers of specifics in sync with the ones in PowerType
+// below.
+message PowerEntity {
+  oneof entity {
+    // Used for notes.
+    NoteEntity note_entity = 2;
+  }
+}
+
+message PowerBookmarkSpecifics {
+  // PowerType is persisted to disk and therefore shouldn't be reoderered or
+  // changed.
+  // Should keep the field numbers of PowerType in sync with the ones in
+  // entity above.
+  enum PowerType {
+    // All powers should have type so this should be unused.
+    POWER_TYPE_UNSPECIFIED = 0;
+    // Used for testing.
+    POWER_TYPE_MOCK = 1;
+    // Used for notes.
+    POWER_TYPE_NOTE = 2;
+  }
+
+  // The primary key for local storage.
+  /* required */ optional string guid = 1;
+
+  // Powers associated with a URL.
+  /* required */ optional string url = 2;
+
+  // Tracks the type of the power.
+  /* required */ optional PowerType power_type = 3;
+
+  // Tracks when this was added.
+  /* required */ optional int64 creation_time_usec = 4;
+
+  // Tracks when this was last modified.
+  /* required */ optional int64 update_time_usec = 5;
+
+  // Power entity.
+  /* required */ optional PowerEntity power_entity = 100;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/preference_specifics.proto b/pyhindsight/lib/components/sync/protocol/preference_specifics.proto
new file mode 100644
index 0000000..98bad40
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/preference_specifics.proto
@@ -0,0 +1,23 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for preferences.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of preference sync objects.
+message PreferenceSpecifics {
+  optional string name = 1;
+  optional string value = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/prepare_full_proto.py b/pyhindsight/lib/components/sync/protocol/prepare_full_proto.py
new file mode 100644
index 0000000..ca0d88b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/prepare_full_proto.py
@@ -0,0 +1,86 @@
+# Copyright 2025 The Chromium Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os
+import re
+import sys
+
+
+def process_proto_file(input_path, output_path, local_import_basenames):
+  """Reads an input .proto file and writes a processed version.
+
+  Transformations:
+  1. Removes 'option optimize_for = LITE_RUNTIME;'.
+  2. Uncomments blocks between '// copybara:uncomment_begin/end'.
+  3. Rewrites any import statement that points to another file being processed
+     in the same batch to use the "_full_proto.proto" suffix.
+  """
+  # Regex to find and capture the path in an import statement.
+  import_regex = re.compile(r'import\s+"([^"]+\.proto)"')
+
+  # Ensure the output directory exists.
+  os.makedirs(os.path.dirname(output_path), exist_ok=True)
+
+  with open(input_path, "r") as f_in, open(output_path, "w") as f_out:
+    in_annotation_block = False
+    for line in f_in:
+      # Rule 1: Remove LITE_RUNTIME option.
+      if "option optimize_for = LITE_RUNTIME;" in line:
+        continue
+
+      # Rule 2: Handle annotation blocks.
+      if "copybara:uncomment_begin" in line:
+        in_annotation_block = True
+        continue
+      if "copybara:uncomment_end" in line:
+        in_annotation_block = False
+        continue
+
+      # If we are in an annotation block, uncomment the line before
+      # further processing.
+      if in_annotation_block:
+        line = re.sub(r"^(\s*)//\s?(.*)$", r"\1\2", line)
+
+      # Rule 3: Rewrite local imports to use the "_full_proto" suffix.
+      match = import_regex.search(line)
+      # Check if this line is an import and if the file it imports is one
+      # of the other files we are processing in this batch.
+      if match and os.path.basename(match.group(1)) in local_import_basenames:
+        original_import_path = match.group(1)
+        new_import_path = original_import_path.replace(
+            ".proto", "_full_proto.proto"
+        )
+        line = f'import "{new_import_path}";\n'
+
+      f_out.write(line)
+
+
+def main():
+  """Main function to handle command-line arguments.
+
+  It now correctly parses the arguments provided by the BUILD.gn action.
+  """
+  if len(sys.argv) < 3:
+    print(
+        "Usage: python3 prepare_full_proto.py <output_dir>"
+        " <full_input_path1> ..."
+    )
+    sys.exit(1)
+
+  output_dir = sys.argv[1]
+
+  input_paths = sys.argv[2:]
+
+  local_import_basenames = {os.path.basename(p) for p in input_paths}
+
+  for input_path in input_paths:
+    output_basename = os.path.basename(input_path).replace(
+        ".proto", "_full_proto.proto"
+    )
+    output_path = os.path.join(output_dir, output_basename)
+    process_proto_file(input_path, output_path, local_import_basenames)
+
+
+if __name__ == "__main__":
+  main()
diff --git a/pyhindsight/lib/components/sync/protocol/printer_specifics.proto b/pyhindsight/lib/components/sync/protocol/printer_specifics.proto
new file mode 100644
index 0000000..e202605
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/printer_specifics.proto
@@ -0,0 +1,81 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for printer data.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// User PPD configuration
+message PrinterPPDReference {
+  // Url for user provided file.  Overrides other fields.
+  optional string user_supplied_ppd_url = 1;
+
+  // Retired fields
+  optional string effective_manufacturer = 2 [deprecated = true];
+  optional string effective_model = 3 [deprecated = true];
+
+  // String identifying the type of printer, used to look up a ppd to drive the
+  // printer.
+  optional string effective_make_and_model = 4;
+
+  // True if the printer should be automatically configured, false otherwise.
+  optional bool autoconf = 5 [default = false];
+}
+
+message PrinterSpecifics {
+  // Printer record GUID
+  optional string id = 1;
+
+  // User visible name.  Any string.
+  optional string display_name = 2;
+
+  // User visible description.  Any string.
+  optional string description = 3;
+
+  // Printer manufacturer.  Should be a known manufacturuer.
+  // Deprecated in favor of make_and_model.
+  optional string manufacturer = 4 [deprecated = true];
+
+  // Printer model.  Should match a known model for the manufacturer.
+  // Deprecated in favor of make_and_model.
+  optional string model = 5 [deprecated = true];
+
+  // Universal Resource Identifier for the printer on the network.  usb:// will
+  // be the scheme for USB printers.  Example
+  // ipp://address.example:port/queue/queue/queue.
+  optional string uri = 6;
+
+  // Universally Unique Identifier provided by the printer.  Used for unique
+  // identification of printers in a zeroconf environment.
+  optional string uuid = 7;
+
+  // PPDData was deprecated in favor of PPDReference format.
+  optional bytes ppd = 8 [deprecated = true];
+
+  // Structure representing the user's ppd configuration.
+  optional PrinterPPDReference ppd_reference = 9;
+
+  // Timestamp when printer was last updated.
+  optional int64 updated_timestamp = 10;
+
+  // The make and model of the printer in one string.  The typical arrangement
+  // for this is '<make> <model>'.  This aligns with the typical formatting of
+  // the IPP attribute printer-make-and-model.
+  optional string make_and_model = 11;
+
+  // Universal Resource Identifier for the print server on the network.  This
+  // will only be populated if the printer is from a print server.  Example
+  // ipp://address.example:port/
+  optional string print_server_uri = 12;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/printers_authorization_server_specifics.proto b/pyhindsight/lib/components/sync/protocol/printers_authorization_server_specifics.proto
new file mode 100644
index 0000000..c73b72e
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/printers_authorization_server_specifics.proto
@@ -0,0 +1,25 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for printer data.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Represents trusted Authorization Server for printers.
+message PrintersAuthorizationServerSpecifics {
+  // Universal Resource Identifier for the authorization server on the network.
+  // The scheme must be https. Example: https://address.example:port/path/path.
+  // This field must be unique and is required.
+  optional string uri = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/priority_preference_specifics.proto b/pyhindsight/lib/components/sync/protocol/priority_preference_specifics.proto
new file mode 100644
index 0000000..d31cda2
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/priority_preference_specifics.proto
@@ -0,0 +1,24 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for priority preferences.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/preference_specifics.proto";
+
+// Properties of a synced priority preference.
+message PriorityPreferenceSpecifics {
+  optional PreferenceSpecifics preference = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/product_comparison_specifics.proto b/pyhindsight/lib/components/sync/protocol/product_comparison_specifics.proto
new file mode 100644
index 0000000..a4454e0
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/product_comparison_specifics.proto
@@ -0,0 +1,74 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+// Sync protocol datatype extension for compare.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/unique_position.proto";
+
+// A Product Comparison sync entity, containing sufficient data to enable all
+// data acquisition for rendering the Compare experience.
+message ProductComparisonSpecifics {
+  // The primary key for local storage.
+  optional string uuid = 1;
+
+  // Tracks when this entity was created (milliseconds since epoch).
+  optional int64 creation_time_unix_epoch_millis = 2;
+
+  // Tracks when this entity was last modified (milliseconds since epoch).
+  optional int64 update_time_unix_epoch_millis = 3;
+
+  // The name of the comparison group. Will de deprecated in favor of
+  // ProductComparison#name.
+  optional string name = 4;
+
+  // The list of product URLs that constitute this comparison group. Will be
+  // deprecated in favor of ProductComparisonItem#url.
+  repeated ComparisonData data = 5;
+
+  // For splitting out a Product Comparison into multiple specifics.
+  oneof entity {
+    ProductComparison product_comparison = 6;
+    ProductComparisonItem product_comparison_item = 7;
+  }
+}
+
+message ComparisonData {
+  // The URL of the item in the comparison.
+  optional string url = 1;
+}
+
+// Product Comparison specific - top level data about the product comparison.
+message ProductComparison {
+  // Name of this Product Comparison
+  optional string name = 1;
+}
+
+// Product Comparison Item specific - data about one item in the product
+// comparison.
+message ProductComparisonItem {
+  // Identifier of top level ProductComparison specifics this item belongs to
+  optional string product_comparison_uuid = 1;
+
+  // URL for product comparison.
+  optional string url = 2;
+
+  // Ensures unique ordering among items in a product comparison. This is
+  // necessary because the ProductComparisonItems point to a ProductComparison
+  // and not the opposite, so we need to explicitly define the ordering.
+  optional UniquePosition unique_position = 3;
+
+  // Title for the URL for the product comparison item.
+  optional string title = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/proto_enum_conversions.cc b/pyhindsight/lib/components/sync/protocol/proto_enum_conversions.cc
new file mode 100644
index 0000000..9eae644
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_enum_conversions.cc
@@ -0,0 +1,1092 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/proto_enum_conversions.h"
+
+#include "base/logging.h"
+#include "base/notreached.h"
+
+namespace syncer {
+
+#define ASSERT_ENUM_BOUNDS(enum_parent, enum_type, enum_min, enum_max) \
+  static_assert(enum_parent::enum_type##_MIN == enum_parent::enum_min, \
+                #enum_type "_MIN should be " #enum_min);               \
+  static_assert(enum_parent::enum_type##_MAX == enum_parent::enum_max, \
+                #enum_type "_MAX should be " #enum_max);
+
+#define ENUM_CASE(enum_parent, enum_value) \
+  case enum_parent::enum_value:            \
+    return #enum_value
+
+const char* ProtoEnumToString(
+    sync_pb::AppListSpecifics::AppListItemType item_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::AppListSpecifics, AppListItemType, TYPE_APP,
+                     TYPE_PAGE_BREAK);
+  switch (item_type) {
+    ENUM_CASE(sync_pb::AppListSpecifics, TYPE_APP);
+    ENUM_CASE(sync_pb::AppListSpecifics, TYPE_REMOVE_DEFAULT_APP);
+    ENUM_CASE(sync_pb::AppListSpecifics, TYPE_FOLDER);
+    ENUM_CASE(sync_pb::AppListSpecifics, TYPE_OBSOLETE_URL);
+    ENUM_CASE(sync_pb::AppListSpecifics, TYPE_PAGE_BREAK);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::AppSpecifics::LaunchType launch_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::AppSpecifics, LaunchType, PINNED, WINDOW);
+  switch (launch_type) {
+    ENUM_CASE(sync_pb::AppSpecifics, PINNED);
+    ENUM_CASE(sync_pb::AppSpecifics, REGULAR);
+    ENUM_CASE(sync_pb::AppSpecifics, FULLSCREEN);
+    ENUM_CASE(sync_pb::AppSpecifics, WINDOW);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::AutofillProfileSpecifics::VerificationStatus status) {
+  ASSERT_ENUM_BOUNDS(sync_pb::AutofillProfileSpecifics, VerificationStatus,
+                     VERIFICATION_STATUS_UNSPECIFIED, SERVER_PARSED);
+  switch (status) {
+    ENUM_CASE(sync_pb::AutofillProfileSpecifics,
+              VERIFICATION_STATUS_UNSPECIFIED);
+    ENUM_CASE(sync_pb::AutofillProfileSpecifics, PARSED);
+    ENUM_CASE(sync_pb::AutofillProfileSpecifics, FORMATTED);
+    ENUM_CASE(sync_pb::AutofillProfileSpecifics, OBSERVED);
+    ENUM_CASE(sync_pb::AutofillProfileSpecifics, USER_VERIFIED);
+    ENUM_CASE(sync_pb::AutofillProfileSpecifics, SERVER_PARSED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::AutofillWalletSpecifics::WalletInfoType wallet_info_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::AutofillWalletSpecifics, WalletInfoType, UNKNOWN,
+                     PAYMENT_INSTRUMENT_CREATION_OPTION);
+  switch (wallet_info_type) {
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, UNKNOWN);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, MASKED_CREDIT_CARD);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, POSTAL_ADDRESS);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, CUSTOMER_DATA);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, CREDIT_CARD_CLOUD_TOKEN_DATA);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, PAYMENT_INSTRUMENT);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics, MASKED_IBAN);
+    ENUM_CASE(sync_pb::AutofillWalletSpecifics,
+              PAYMENT_INSTRUMENT_CREATION_OPTION);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::BankAccountDetails::AccountType account_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::BankAccountDetails, AccountType,
+                     ACCOUNT_TYPE_UNSPECIFIED, TRANSACTING_ACCOUNT);
+  switch (account_type) {
+    ENUM_CASE(sync_pb::BankAccountDetails, ACCOUNT_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::BankAccountDetails, CHECKING);
+    ENUM_CASE(sync_pb::BankAccountDetails, SAVINGS);
+    ENUM_CASE(sync_pb::BankAccountDetails, CURRENT);
+    ENUM_CASE(sync_pb::BankAccountDetails, SALARY);
+    ENUM_CASE(sync_pb::BankAccountDetails, TRANSACTING_ACCOUNT);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::BookmarkSpecifics::Type type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::BookmarkSpecifics, Type, UNSPECIFIED, FOLDER);
+  switch (type) {
+    ENUM_CASE(sync_pb::BookmarkSpecifics, UNSPECIFIED);
+    ENUM_CASE(sync_pb::BookmarkSpecifics, URL);
+    ENUM_CASE(sync_pb::BookmarkSpecifics, FOLDER);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::CommitResponse::ResponseType response_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CommitResponse, ResponseType, SUCCESS,
+                     TRANSIENT_ERROR);
+  switch (response_type) {
+    ENUM_CASE(sync_pb::CommitResponse, SUCCESS);
+    ENUM_CASE(sync_pb::CommitResponse, CONFLICT);
+    ENUM_CASE(sync_pb::CommitResponse, RETRY);
+    ENUM_CASE(sync_pb::CommitResponse, INVALID_MESSAGE);
+    ENUM_CASE(sync_pb::CommitResponse, OVER_QUOTA);
+    ENUM_CASE(sync_pb::CommitResponse, TRANSIENT_ERROR);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::ContactInfoSpecifics::AddressType address_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::ContactInfoSpecifics, AddressType, REGULAR, WORK);
+  switch (address_type) {
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, REGULAR);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, HOME);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, WORK);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::ContactInfoSpecifics::VerificationStatus verification_status) {
+  ASSERT_ENUM_BOUNDS(sync_pb::ContactInfoSpecifics, VerificationStatus,
+                     VERIFICATION_STATUS_UNSPECIFIED, SERVER_PARSED);
+  switch (verification_status) {
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, VERIFICATION_STATUS_UNSPECIFIED);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, PARSED);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, FORMATTED);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, OBSERVED);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, USER_VERIFIED);
+    ENUM_CASE(sync_pb::ContactInfoSpecifics, SERVER_PARSED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::TrustedVaultAutoUpgradeExperimentGroup::Type type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::TrustedVaultAutoUpgradeExperimentGroup, Type,
+                     TYPE_UNSPECIFIED, VALIDATION);
+
+  switch (type) {
+    ENUM_CASE(sync_pb::TrustedVaultAutoUpgradeExperimentGroup,
+              TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::TrustedVaultAutoUpgradeExperimentGroup, TREATMENT);
+    ENUM_CASE(sync_pb::TrustedVaultAutoUpgradeExperimentGroup, CONTROL);
+    ENUM_CASE(sync_pb::TrustedVaultAutoUpgradeExperimentGroup, VALIDATION);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::NigoriSpecifics::PassphraseType type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::NigoriSpecifics, PassphraseType, UNKNOWN,
+                     TRUSTED_VAULT_PASSPHRASE);
+  switch (type) {
+    ENUM_CASE(sync_pb::NigoriSpecifics, UNKNOWN);
+    ENUM_CASE(sync_pb::NigoriSpecifics, IMPLICIT_PASSPHRASE);
+    ENUM_CASE(sync_pb::NigoriSpecifics, KEYSTORE_PASSPHRASE);
+    ENUM_CASE(sync_pb::NigoriSpecifics, FROZEN_IMPLICIT_PASSPHRASE);
+    ENUM_CASE(sync_pb::NigoriSpecifics, CUSTOM_PASSPHRASE);
+    ENUM_CASE(sync_pb::NigoriSpecifics, TRUSTED_VAULT_PASSPHRASE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::PaymentInstrument::SupportedRail supported_rail) {
+  ASSERT_ENUM_BOUNDS(sync_pb::PaymentInstrument, SupportedRail,
+                     SUPPORTED_RAIL_UNKNOWN, CARD_NUMBER);
+  switch (supported_rail) {
+    ENUM_CASE(sync_pb::PaymentInstrument, SUPPORTED_RAIL_UNKNOWN);
+    ENUM_CASE(sync_pb::PaymentInstrument, PIX);
+    ENUM_CASE(sync_pb::PaymentInstrument, IBAN);
+    ENUM_CASE(sync_pb::PaymentInstrument, PAYMENT_HYPERLINK);
+    ENUM_CASE(sync_pb::PaymentInstrument, CARD_NUMBER);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::PaymentInstrument::ActionRequired action_required) {
+  ASSERT_ENUM_BOUNDS(sync_pb::PaymentInstrument, ActionRequired,
+                     ACTION_REQUIRED_UNKNOWN, ACCEPT_TOS);
+  switch (action_required) {
+    ENUM_CASE(sync_pb::PaymentInstrument, ACTION_REQUIRED_UNKNOWN);
+    ENUM_CASE(sync_pb::PaymentInstrument, ACCEPT_TOS);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::PowerBookmarkSpecifics::PowerType power_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::PowerBookmarkSpecifics, PowerType,
+                     POWER_TYPE_UNSPECIFIED, POWER_TYPE_NOTE);
+  switch (power_type) {
+    ENUM_CASE(sync_pb::PowerBookmarkSpecifics, POWER_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::PowerBookmarkSpecifics, POWER_TYPE_MOCK);
+    ENUM_CASE(sync_pb::PowerBookmarkSpecifics, POWER_TYPE_NOTE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::NoteEntity::TargetType target_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::NoteEntity, TargetType, TARGET_TYPE_UNSPECIFIED,
+                     TARGET_TYPE_PAGE);
+  switch (target_type) {
+    ENUM_CASE(sync_pb::NoteEntity, TARGET_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::NoteEntity, TARGET_TYPE_PAGE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::ReadingListSpecifics::ReadingListEntryStatus status) {
+  ASSERT_ENUM_BOUNDS(sync_pb::ReadingListSpecifics, ReadingListEntryStatus,
+                     UNREAD, UNSEEN);
+  switch (status) {
+    ENUM_CASE(sync_pb::ReadingListSpecifics, UNREAD);
+    ENUM_CASE(sync_pb::ReadingListSpecifics, READ);
+    ENUM_CASE(sync_pb::ReadingListSpecifics, UNSEEN);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SavedTabGroup::SavedTabGroupColor color) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SavedTabGroup, SavedTabGroupColor,
+                     SAVED_TAB_GROUP_COLOR_UNSPECIFIED,
+                     SAVED_TAB_GROUP_COLOR_ORANGE);
+  switch (color) {
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_GREY);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_BLUE);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_RED);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_YELLOW);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_GREEN);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_PINK);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_PURPLE);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_CYAN);
+    ENUM_CASE(sync_pb::SavedTabGroup, SAVED_TAB_GROUP_COLOR_ORANGE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SearchEngineSpecifics::ActiveStatus is_active) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SearchEngineSpecifics, ActiveStatus,
+                     ACTIVE_STATUS_UNSPECIFIED, ACTIVE_STATUS_FALSE);
+  switch (is_active) {
+    ENUM_CASE(sync_pb::SearchEngineSpecifics, ACTIVE_STATUS_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SearchEngineSpecifics, ACTIVE_STATUS_TRUE);
+    ENUM_CASE(sync_pb::SearchEngineSpecifics, ACTIVE_STATUS_FALSE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SessionTab::FaviconType favicon_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SessionTab, FaviconType, TYPE_WEB_FAVICON,
+                     TYPE_WEB_FAVICON);
+  switch (favicon_type) { ENUM_CASE(sync_pb::SessionTab, TYPE_WEB_FAVICON); }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SharedTabGroup::Color color) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SharedTabGroup, Color, UNSPECIFIED, ORANGE);
+  switch (color) {
+    ENUM_CASE(sync_pb::SharedTabGroup, UNSPECIFIED);
+    ENUM_CASE(sync_pb::SharedTabGroup, GREY);
+    ENUM_CASE(sync_pb::SharedTabGroup, BLUE);
+    ENUM_CASE(sync_pb::SharedTabGroup, RED);
+    ENUM_CASE(sync_pb::SharedTabGroup, YELLOW);
+    ENUM_CASE(sync_pb::SharedTabGroup, GREEN);
+    ENUM_CASE(sync_pb::SharedTabGroup, PINK);
+    ENUM_CASE(sync_pb::SharedTabGroup, PURPLE);
+    ENUM_CASE(sync_pb::SharedTabGroup, CYAN);
+    ENUM_CASE(sync_pb::SharedTabGroup, ORANGE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::BrowserType browser_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, BrowserType, BROWSER_TYPE_UNKNOWN,
+                     TYPE_AUTH_TAB);
+  switch (browser_type) {
+    ENUM_CASE(sync_pb::SyncEnums, BROWSER_TYPE_UNKNOWN);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_TABBED);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_POPUP);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_CUSTOM_TAB);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_AUTH_TAB);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::Action action) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, Action, UPGRADE_CLIENT,
+                     UNKNOWN_ACTION);
+  switch (action) {
+    ENUM_CASE(sync_pb::SyncEnums, UPGRADE_CLIENT);
+    ENUM_CASE(sync_pb::SyncEnums, UNKNOWN_ACTION);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::DeviceType device_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, DeviceType, TYPE_UNSET, TYPE_TABLET);
+  switch (device_type) {
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_UNSET);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_WIN);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_MAC);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_LINUX);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_CROS);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_OTHER);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_PHONE);
+    ENUM_CASE(sync_pb::SyncEnums, TYPE_TABLET);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::OsType os_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, OsType, OS_TYPE_UNSPECIFIED,
+                     OS_TYPE_FUCHSIA);
+  switch (os_type) {
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_WINDOWS);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_MAC);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_LINUX);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_CHROME_OS_ASH);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_ANDROID);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_IOS);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_CHROME_OS_LACROS);
+    ENUM_CASE(sync_pb::SyncEnums, OS_TYPE_FUCHSIA);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::DeviceFormFactor device_form_factor) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, DeviceFormFactor,
+                     DEVICE_FORM_FACTOR_UNSPECIFIED, DEVICE_FORM_FACTOR_TV);
+  switch (device_form_factor) {
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_DESKTOP);
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_PHONE);
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_TABLET);
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_AUTOMOTIVE);
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_WEARABLE);
+    ENUM_CASE(sync_pb::SyncEnums, DEVICE_FORM_FACTOR_TV);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::ErrorType error_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, ErrorType, SUCCESS, UNKNOWN);
+  switch (error_type) {
+    ENUM_CASE(sync_pb::SyncEnums, SUCCESS);
+    ENUM_CASE(sync_pb::SyncEnums, NOT_MY_BIRTHDAY);
+    ENUM_CASE(sync_pb::SyncEnums, THROTTLED);
+    ENUM_CASE(sync_pb::SyncEnums, TRANSIENT_ERROR);
+    ENUM_CASE(sync_pb::SyncEnums, MIGRATION_DONE);
+    ENUM_CASE(sync_pb::SyncEnums, DISABLED_BY_ADMIN);
+    ENUM_CASE(sync_pb::SyncEnums, PARTIAL_FAILURE);
+    ENUM_CASE(sync_pb::SyncEnums, CLIENT_DATA_OBSOLETE);
+    ENUM_CASE(sync_pb::SyncEnums, ENCRYPTION_OBSOLETE);
+    ENUM_CASE(sync_pb::SyncEnums, UNKNOWN);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::GetUpdatesOrigin origin) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, GetUpdatesOrigin, UNKNOWN_ORIGIN,
+                     PROGRAMMATIC);
+  switch (origin) {
+    ENUM_CASE(sync_pb::SyncEnums, UNKNOWN_ORIGIN);
+    ENUM_CASE(sync_pb::SyncEnums, PERIODIC);
+    ENUM_CASE(sync_pb::SyncEnums, NEWLY_SUPPORTED_DATATYPE);
+    ENUM_CASE(sync_pb::SyncEnums, MIGRATION);
+    ENUM_CASE(sync_pb::SyncEnums, NEW_CLIENT);
+    ENUM_CASE(sync_pb::SyncEnums, RECONFIGURATION);
+    ENUM_CASE(sync_pb::SyncEnums, GU_TRIGGER);
+    ENUM_CASE(sync_pb::SyncEnums, PROGRAMMATIC);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::PageTransition page_transition) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, PageTransition, LINK,
+                     KEYWORD_GENERATED);
+  switch (page_transition) {
+    ENUM_CASE(sync_pb::SyncEnums, LINK);
+    ENUM_CASE(sync_pb::SyncEnums, TYPED);
+    ENUM_CASE(sync_pb::SyncEnums, AUTO_BOOKMARK);
+    ENUM_CASE(sync_pb::SyncEnums, AUTO_SUBFRAME);
+    ENUM_CASE(sync_pb::SyncEnums, MANUAL_SUBFRAME);
+    ENUM_CASE(sync_pb::SyncEnums, GENERATED);
+    ENUM_CASE(sync_pb::SyncEnums, AUTO_TOPLEVEL);
+    ENUM_CASE(sync_pb::SyncEnums, FORM_SUBMIT);
+    ENUM_CASE(sync_pb::SyncEnums, RELOAD);
+    ENUM_CASE(sync_pb::SyncEnums, KEYWORD);
+    ENUM_CASE(sync_pb::SyncEnums, KEYWORD_GENERATED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::PageTransitionRedirectType page_transition_qualifier) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, PageTransitionRedirectType,
+                     CLIENT_REDIRECT, SERVER_REDIRECT);
+  switch (page_transition_qualifier) {
+    ENUM_CASE(sync_pb::SyncEnums, CLIENT_REDIRECT);
+    ENUM_CASE(sync_pb::SyncEnums, SERVER_REDIRECT);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::SendTabReceivingType send_tab_receiving_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, SendTabReceivingType,
+                     SEND_TAB_RECEIVING_TYPE_CHROME_OR_UNSPECIFIED,
+                     SEND_TAB_RECEIVING_TYPE_CHROME_AND_PUSH_NOTIFICATION);
+  switch (send_tab_receiving_type) {
+    ENUM_CASE(sync_pb::SyncEnums,
+              SEND_TAB_RECEIVING_TYPE_CHROME_OR_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SyncEnums,
+              SEND_TAB_RECEIVING_TYPE_CHROME_AND_PUSH_NOTIFICATION);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::SingletonDebugEventType type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, SingletonDebugEventType,
+                     CONNECTION_STATUS_CHANGE, TRUSTED_VAULT_KEY_ACCEPTED);
+  switch (type) {
+    ENUM_CASE(sync_pb::SyncEnums, CONNECTION_STATUS_CHANGE);
+    ENUM_CASE(sync_pb::SyncEnums, UPDATED_TOKEN);
+    ENUM_CASE(sync_pb::SyncEnums, PASSPHRASE_REQUIRED);
+    ENUM_CASE(sync_pb::SyncEnums, PASSPHRASE_ACCEPTED);
+    ENUM_CASE(sync_pb::SyncEnums, INITIALIZATION_COMPLETE);
+    ENUM_CASE(sync_pb::SyncEnums, STOP_SYNCING_PERMANENTLY);
+    ENUM_CASE(sync_pb::SyncEnums, ACTIONABLE_ERROR);
+    ENUM_CASE(sync_pb::SyncEnums, ENCRYPTED_TYPES_CHANGED);
+    ENUM_CASE(sync_pb::SyncEnums, PASSPHRASE_TYPE_CHANGED);
+    ENUM_CASE(sync_pb::SyncEnums, DEPRECATED_KEYSTORE_TOKEN_UPDATED);
+    ENUM_CASE(sync_pb::SyncEnums, CONFIGURE_COMPLETE);
+    ENUM_CASE(sync_pb::SyncEnums, DEPRECATED_BOOTSTRAP_TOKEN_UPDATED);
+    ENUM_CASE(sync_pb::SyncEnums, TRUSTED_VAULT_KEY_REQUIRED);
+    ENUM_CASE(sync_pb::SyncEnums, TRUSTED_VAULT_KEY_ACCEPTED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::TabNavigation::BlockedState state) {
+  ASSERT_ENUM_BOUNDS(sync_pb::TabNavigation, BlockedState, STATE_ALLOWED,
+                     STATE_BLOCKED);
+  switch (state) {
+    ENUM_CASE(sync_pb::TabNavigation, STATE_ALLOWED);
+    ENUM_CASE(sync_pb::TabNavigation, STATE_BLOCKED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::PasswordState state) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SyncEnums, PasswordState, PASSWORD_STATE_UNKNOWN,
+                     HAS_PASSWORD_FIELD);
+  switch (state) {
+    ENUM_CASE(sync_pb::SyncEnums, PASSWORD_STATE_UNKNOWN);
+    ENUM_CASE(sync_pb::SyncEnums, NO_PASSWORD_FIELD);
+    ENUM_CASE(sync_pb::SyncEnums, HAS_PASSWORD_FIELD);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::UserConsentTypes::ConsentStatus status) {
+  ASSERT_ENUM_BOUNDS(sync_pb::UserConsentTypes, ConsentStatus,
+                     CONSENT_STATUS_UNSPECIFIED, GIVEN);
+  switch (status) {
+    ENUM_CASE(sync_pb::UserConsentTypes, CONSENT_STATUS_UNSPECIFIED);
+    ENUM_CASE(sync_pb::UserConsentTypes, NOT_GIVEN);
+    ENUM_CASE(sync_pb::UserConsentTypes, GIVEN);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus::
+        ReportingPopulation safe_browsing_reporting_population) {
+  ASSERT_ENUM_BOUNDS(
+      sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus,
+      ReportingPopulation, REPORTING_POPULATION_UNSPECIFIED,
+      ENHANCED_PROTECTION);
+  switch (safe_browsing_reporting_population) {
+    ENUM_CASE(
+        sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus,
+        REPORTING_POPULATION_UNSPECIFIED);
+    ENUM_CASE(
+        sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus,
+        NONE);
+    ENUM_CASE(
+        sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus,
+        EXTENDED_REPORTING);
+    ENUM_CASE(
+        sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus,
+        SCOUT);
+    ENUM_CASE(
+        sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus,
+        ENHANCED_PROTECTION);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction::
+        InteractionResult interaction_result) {
+  ASSERT_ENUM_BOUNDS(sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction,
+                     InteractionResult, UNSPECIFIED,
+                     WARNING_ACTION_TAKEN_ON_SETTINGS);
+  switch (interaction_result) {
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction,
+              UNSPECIFIED);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction,
+              WARNING_ACTION_TAKEN);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction,
+              WARNING_ACTION_IGNORED);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction,
+              WARNING_UI_IGNORED);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction,
+              WARNING_ACTION_TAKEN_ON_SETTINGS);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseLookup::LookupResult
+        lookup_result) {
+  ASSERT_ENUM_BOUNDS(sync_pb::GaiaPasswordReuse::PasswordReuseLookup,
+                     LookupResult, UNSPECIFIED, TURNED_OFF_BY_POLICY);
+  switch (lookup_result) {
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, UNSPECIFIED);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, ALLOWLIST_HIT);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, CACHE_HIT);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, REQUEST_SUCCESS);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, REQUEST_FAILURE);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, URL_UNSUPPORTED);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup,
+              ENTERPRISE_ALLOWLIST_HIT);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup,
+              TURNED_OFF_BY_POLICY);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseLookup::ReputationVerdict
+        verdict) {
+  ASSERT_ENUM_BOUNDS(sync_pb::GaiaPasswordReuse::PasswordReuseLookup,
+                     ReputationVerdict, VERDICT_UNSPECIFIED, PHISHING);
+  switch (verdict) {
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup,
+              VERDICT_UNSPECIFIED);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, SAFE);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, LOW_REPUTATION);
+    ENUM_CASE(sync_pb::GaiaPasswordReuse::PasswordReuseLookup, PHISHING);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::UserEventSpecifics::GaiaPasswordCaptured::EventTrigger trigger) {
+  ASSERT_ENUM_BOUNDS(sync_pb::UserEventSpecifics::GaiaPasswordCaptured,
+                     EventTrigger, UNSPECIFIED, EXPIRED_28D_TIMER);
+  switch (trigger) {
+    ENUM_CASE(sync_pb::UserEventSpecifics::GaiaPasswordCaptured, UNSPECIFIED);
+    ENUM_CASE(sync_pb::UserEventSpecifics::GaiaPasswordCaptured,
+              USER_LOGGED_IN);
+    ENUM_CASE(sync_pb::UserEventSpecifics::GaiaPasswordCaptured,
+              EXPIRED_28D_TIMER);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::UserEventSpecifics::FlocIdComputed::EventTrigger trigger) {
+  ASSERT_ENUM_BOUNDS(sync_pb::UserEventSpecifics::FlocIdComputed, EventTrigger,
+                     UNSPECIFIED, HISTORY_DELETE);
+  switch (trigger) {
+    ENUM_CASE(sync_pb::UserEventSpecifics::FlocIdComputed, UNSPECIFIED);
+    ENUM_CASE(sync_pb::UserEventSpecifics::FlocIdComputed, NEW);
+    ENUM_CASE(sync_pb::UserEventSpecifics::FlocIdComputed, REFRESHED);
+    ENUM_CASE(sync_pb::UserEventSpecifics::FlocIdComputed, HISTORY_DELETE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::CardInfoRetrievalEnrollmentState
+        card_info_retrieval_enrollment_state) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard,
+                     CardInfoRetrievalEnrollmentState, RETRIEVAL_UNSPECIFIED,
+                     RETRIEVAL_UNENROLLED_AND_ELIGIBLE);
+  switch (card_info_retrieval_enrollment_state) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, RETRIEVAL_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, RETRIEVAL_ENROLLED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard,
+              RETRIEVAL_UNENROLLED_AND_NOT_ELIGIBLE);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard,
+              RETRIEVAL_UNENROLLED_AND_ELIGIBLE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::CardBenefitSource card_benefit_source) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard, CardBenefitSource, SOURCE_UNKNOWN,
+                     SOURCE_CURINOS);
+  switch (card_benefit_source) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, SOURCE_UNKNOWN);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, SOURCE_AMEX);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, SOURCE_BMO);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, SOURCE_CURINOS);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::CardCreationSource card_creation_source) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard, CardCreationSource,
+                     CREATION_SOURCE_UNSPECIFIED,
+                     CREATION_SOURCE_NON_CHROME_PAYMENTS);
+  switch (card_creation_source) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, CREATION_SOURCE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, CREATION_SOURCE_CHROME_PAYMENTS);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard,
+              CREATION_SOURCE_NON_CHROME_PAYMENTS);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::VirtualCardEnrollmentState
+        virtual_card_enrollment_state) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard,
+                     VirtualCardEnrollmentState, UNSPECIFIED,
+                     UNENROLLED_AND_ELIGIBLE);
+  switch (virtual_card_enrollment_state) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, UNSPECIFIED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, UNENROLLED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, ENROLLED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, UNENROLLED_AND_NOT_ELIGIBLE);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, UNENROLLED_AND_ELIGIBLE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::VirtualCardEnrollmentType
+        virtual_card_enrollment_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard, VirtualCardEnrollmentType,
+                     TYPE_UNSPECIFIED, NETWORK);
+  switch (virtual_card_enrollment_type) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, ISSUER);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, NETWORK);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::WalletCardStatus wallet_card_status) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard, WalletCardStatus, VALID,
+                     EXPIRED);
+  switch (wallet_card_status) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, VALID);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, EXPIRED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::WalletCardType wallet_card_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMaskedCreditCard, WalletCardType, UNKNOWN,
+                     VERVE);
+  switch (wallet_card_type) {
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, UNKNOWN);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, AMEX);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, DISCOVER);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, JCB);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, MAESTRO);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, MASTER_CARD);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, SOLO);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, SWITCH);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, VISA);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, UNIONPAY);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, ELO);
+    ENUM_CASE(sync_pb::WalletMaskedCreditCard, VERVE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::CardBenefit::CategoryBenefitType category_benefit_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CardBenefit, CategoryBenefitType,
+                     CATEGORY_BENEFIT_TYPE_UNKNOWN, WHOLESALE_CLUBS);
+  switch (category_benefit_type) {
+    ENUM_CASE(sync_pb::CardBenefit, CATEGORY_BENEFIT_TYPE_UNKNOWN);
+    ENUM_CASE(sync_pb::CardBenefit, SUBSCRIPTION);
+    ENUM_CASE(sync_pb::CardBenefit, FLIGHTS);
+    ENUM_CASE(sync_pb::CardBenefit, DINING);
+    ENUM_CASE(sync_pb::CardBenefit, ENTERTAINMENT);
+    ENUM_CASE(sync_pb::CardBenefit, STREAMING);
+    ENUM_CASE(sync_pb::CardBenefit, GROCERY_STORES);
+    ENUM_CASE(sync_pb::CardBenefit, AIR_MILES_PARTNER);
+    ENUM_CASE(sync_pb::CardBenefit, ALCOHOL_STORES);
+    ENUM_CASE(sync_pb::CardBenefit, DRUGSTORES);
+    ENUM_CASE(sync_pb::CardBenefit, OFFICE_SUPPLIES);
+    ENUM_CASE(sync_pb::CardBenefit, RECURRING_BILLS);
+    ENUM_CASE(sync_pb::CardBenefit, TRANSIT);
+    ENUM_CASE(sync_pb::CardBenefit, TRAVEL);
+    ENUM_CASE(sync_pb::CardBenefit, WHOLESALE_CLUBS);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::CardIssuer::Issuer issuer) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CardIssuer, Issuer, ISSUER_UNKNOWN,
+                     EXTERNAL_ISSUER);
+  switch (issuer) {
+    ENUM_CASE(sync_pb::CardIssuer, ISSUER_UNKNOWN);
+    ENUM_CASE(sync_pb::CardIssuer, GOOGLE);
+    ENUM_CASE(sync_pb::CardIssuer, EXTERNAL_ISSUER);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMetadataSpecifics::Type wallet_metadata_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WalletMetadataSpecifics, Type, UNKNOWN, IBAN);
+  switch (wallet_metadata_type) {
+    ENUM_CASE(sync_pb::WalletMetadataSpecifics, UNKNOWN);
+    ENUM_CASE(sync_pb::WalletMetadataSpecifics, CARD);
+    ENUM_CASE(sync_pb::WalletMetadataSpecifics, ADDRESS);
+    ENUM_CASE(sync_pb::WalletMetadataSpecifics, IBAN);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::WebApkIconInfo::Purpose purpose) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WebApkIconInfo, Purpose, UNSPECIFIED, MONOCHROME);
+  switch (purpose) {
+    ENUM_CASE(sync_pb::WebApkIconInfo, UNSPECIFIED);
+    ENUM_CASE(sync_pb::WebApkIconInfo, ANY);
+    ENUM_CASE(sync_pb::WebApkIconInfo, MASKABLE);
+    ENUM_CASE(sync_pb::WebApkIconInfo, MONOCHROME);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::WebAppIconInfo::Purpose purpose) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WebAppIconInfo, Purpose, UNSPECIFIED, MONOCHROME);
+  switch (purpose) {
+    ENUM_CASE(sync_pb::WebAppIconInfo, UNSPECIFIED);
+    ENUM_CASE(sync_pb::WebAppIconInfo, ANY);
+    ENUM_CASE(sync_pb::WebAppIconInfo, MASKABLE);
+    ENUM_CASE(sync_pb::WebAppIconInfo, MONOCHROME);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WebAppSpecifics::UserDisplayMode user_display_mode) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WebAppSpecifics, UserDisplayMode, UNSPECIFIED,
+                     TABBED);
+  switch (user_display_mode) {
+    ENUM_CASE(sync_pb::WebAppSpecifics, UNSPECIFIED);
+    ENUM_CASE(sync_pb::WebAppSpecifics, BROWSER);
+    ENUM_CASE(sync_pb::WebAppSpecifics, STANDALONE);
+    ENUM_CASE(sync_pb::WebAppSpecifics, TABBED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::SecurityType security_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WifiConfigurationSpecifics, SecurityType,
+                     SECURITY_TYPE_UNSPECIFIED, SECURITY_TYPE_PSK);
+  switch (security_type) {
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, SECURITY_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, SECURITY_TYPE_NONE);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, SECURITY_TYPE_WEP);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, SECURITY_TYPE_PSK);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::AutomaticallyConnectOption
+        automatically_connect_option) {
+  ASSERT_ENUM_BOUNDS(
+      sync_pb::WifiConfigurationSpecifics, AutomaticallyConnectOption,
+      AUTOMATICALLY_CONNECT_UNSPECIFIED, AUTOMATICALLY_CONNECT_ENABLED);
+  switch (automatically_connect_option) {
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics,
+              AUTOMATICALLY_CONNECT_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics,
+              AUTOMATICALLY_CONNECT_DISABLED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics,
+              AUTOMATICALLY_CONNECT_ENABLED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::IsPreferredOption
+        is_preferred_option) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WifiConfigurationSpecifics, IsPreferredOption,
+                     IS_PREFERRED_UNSPECIFIED, IS_PREFERRED_ENABLED);
+  switch (is_preferred_option) {
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, IS_PREFERRED_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, IS_PREFERRED_DISABLED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, IS_PREFERRED_ENABLED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::MeteredOption metered_option) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WifiConfigurationSpecifics, MeteredOption,
+                     METERED_OPTION_UNSPECIFIED, METERED_OPTION_AUTO);
+  switch (metered_option) {
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, METERED_OPTION_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, METERED_OPTION_NO);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, METERED_OPTION_YES);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics, METERED_OPTION_AUTO);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::ProxyConfiguration::ProxyOption
+        proxy_option) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WifiConfigurationSpecifics::ProxyConfiguration,
+                     ProxyOption, PROXY_OPTION_UNSPECIFIED,
+                     PROXY_OPTION_MANUAL);
+  switch (proxy_option) {
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics::ProxyConfiguration,
+              PROXY_OPTION_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics::ProxyConfiguration,
+              PROXY_OPTION_DISABLED);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics::ProxyConfiguration,
+              PROXY_OPTION_AUTOMATIC);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics::ProxyConfiguration,
+              PROXY_OPTION_AUTODISCOVERY);
+    ENUM_CASE(sync_pb::WifiConfigurationSpecifics::ProxyConfiguration,
+              PROXY_OPTION_MANUAL);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::WindowState window_state) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WorkspaceDeskSpecifics, WindowState,
+                     UNKNOWN_WINDOW_STATE, FLOATED);
+  switch (window_state) {
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, UNKNOWN_WINDOW_STATE);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, NORMAL);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, MINIMIZED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, MAXIMIZED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, FULLSCREEN);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, PRIMARY_SNAPPED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, SECONDARY_SNAPPED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, FLOATED);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::LaunchContainer container) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WorkspaceDeskSpecifics, LaunchContainer,
+                     LAUNCH_CONTAINER_UNSPECIFIED, LAUNCH_CONTAINER_NONE);
+  switch (container) {
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, LAUNCH_CONTAINER_UNSPECIFIED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, LAUNCH_CONTAINER_WINDOW);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics,
+              LAUNCH_CONTAINER_PANEL_DEPRECATED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, LAUNCH_CONTAINER_TAB);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, LAUNCH_CONTAINER_NONE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::WindowOpenDisposition disposition) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WorkspaceDeskSpecifics, WindowOpenDisposition,
+                     UNKNOWN, NEW_PICTURE_IN_PICTURE);
+  switch (disposition) {
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, UNKNOWN);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, CURRENT_TAB);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, SINGLETON_TAB);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, NEW_FOREGROUND_TAB);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, NEW_BACKGROUND_TAB);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, NEW_POPUP);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, NEW_WINDOW);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, SAVE_TO_DISK);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, OFF_THE_RECORD);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, IGNORE_ACTION);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, SWITCH_TO_TAB);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, NEW_PICTURE_IN_PICTURE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::UserConsentTypes::AssistantActivityControlConsent::SettingType
+        setting_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::UserConsentTypes::AssistantActivityControlConsent,
+                     SettingType, SETTING_TYPE_UNSPECIFIED, DEVICE_APPS);
+  switch (setting_type) {
+    ENUM_CASE(sync_pb::UserConsentTypes::AssistantActivityControlConsent,
+              SETTING_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::UserConsentTypes::AssistantActivityControlConsent, ALL);
+    ENUM_CASE(sync_pb::UserConsentTypes::AssistantActivityControlConsent,
+              WEB_AND_APP_ACTIVITY);
+    ENUM_CASE(sync_pb::UserConsentTypes::AssistantActivityControlConsent,
+              DEVICE_APPS);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::WorkspaceDeskSpecifics::DeskType type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WorkspaceDeskSpecifics, DeskType, UNKNOWN_TYPE,
+                     FLOATING_WORKSPACE);
+  switch (type) {
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, UNKNOWN_TYPE);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, TEMPLATE);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, SAVE_AND_RECALL);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, FLOATING_WORKSPACE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::TabGroupColor color) {
+  ASSERT_ENUM_BOUNDS(sync_pb::WorkspaceDeskSpecifics, TabGroupColor,
+                     UNKNOWN_COLOR, ORANGE);
+
+  switch (color) {
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, UNKNOWN_COLOR);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, GREY);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, BLUE);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, RED);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, YELLOW);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, GREEN);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, PINK);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, PURPLE);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, CYAN);
+    ENUM_CASE(sync_pb::WorkspaceDeskSpecifics, ORANGE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(sync_pb::DataTypeState::InitialSyncState state) {
+  ASSERT_ENUM_BOUNDS(sync_pb::DataTypeState, InitialSyncState,
+                     INITIAL_SYNC_STATE_UNSPECIFIED, INITIAL_SYNC_UNNECESSARY);
+  switch (state) {
+    ENUM_CASE(sync_pb::DataTypeState, INITIAL_SYNC_STATE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::DataTypeState, INITIAL_SYNC_PARTIALLY_DONE);
+    ENUM_CASE(sync_pb::DataTypeState, INITIAL_SYNC_DONE);
+    ENUM_CASE(sync_pb::DataTypeState, INITIAL_SYNC_UNNECESSARY);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookieSameSite site_restrictions) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CookieSpecifics, CookieSameSite, UNSPECIFIED,
+                     STRICT_MODE);
+  switch (site_restrictions) {
+    ENUM_CASE(sync_pb::CookieSpecifics, UNSPECIFIED);
+    ENUM_CASE(sync_pb::CookieSpecifics, NO_RESTRICTION);
+    ENUM_CASE(sync_pb::CookieSpecifics, LAX_MODE);
+    ENUM_CASE(sync_pb::CookieSpecifics, STRICT_MODE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookiePriority priority) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CookieSpecifics, CookiePriority,
+                     UNSPECIFIED_PRIORITY, HIGH);
+  switch (priority) {
+    ENUM_CASE(sync_pb::CookieSpecifics, UNSPECIFIED_PRIORITY);
+    ENUM_CASE(sync_pb::CookieSpecifics, LOW);
+    ENUM_CASE(sync_pb::CookieSpecifics, MEDIUM);
+    ENUM_CASE(sync_pb::CookieSpecifics, HIGH);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookieSourceScheme source_scheme) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CookieSpecifics, CookieSourceScheme, UNSET,
+                     SECURE);
+  switch (source_scheme) {
+    ENUM_CASE(sync_pb::CookieSpecifics, UNSET);
+    ENUM_CASE(sync_pb::CookieSpecifics, NON_SECURE);
+    ENUM_CASE(sync_pb::CookieSpecifics, SECURE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookieSourceType source_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::CookieSpecifics, CookieSourceType, UNKNOWN,
+                     OTHER);
+  switch (source_type) {
+    ENUM_CASE(sync_pb::CookieSpecifics, UNKNOWN);
+    ENUM_CASE(sync_pb::CookieSpecifics, HTTP);
+    ENUM_CASE(sync_pb::CookieSpecifics, SCRIPT);
+    ENUM_CASE(sync_pb::CookieSpecifics, OTHER);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::SharingMessageSpecifics::ChannelConfiguration::
+        ChimeChannelConfiguration::ChimeChannelType channel_type) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SharingMessageSpecifics::ChannelConfiguration::
+                         ChimeChannelConfiguration,
+                     ChimeChannelType, CHANNEL_TYPE_UNSPECIFIED, APPLE_PUSH);
+  switch (channel_type) {
+    ENUM_CASE(sync_pb::SharingMessageSpecifics::ChannelConfiguration::
+                  ChimeChannelConfiguration,
+              CHANNEL_TYPE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SharingMessageSpecifics::ChannelConfiguration::
+                  ChimeChannelConfiguration,
+              APPLE_PUSH);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::UserColorTheme::BrowserColorVariant browser_color_variant) {
+  ASSERT_ENUM_BOUNDS(sync_pb::UserColorTheme, BrowserColorVariant,
+                     BROWSER_COLOR_VARIANT_UNSPECIFIED, EXPRESSIVE);
+  switch (browser_color_variant) {
+    ENUM_CASE(sync_pb::UserColorTheme, BROWSER_COLOR_VARIANT_UNSPECIFIED);
+    ENUM_CASE(sync_pb::UserColorTheme, SYSTEM);
+    ENUM_CASE(sync_pb::UserColorTheme, TONAL_SPOT);
+    ENUM_CASE(sync_pb::UserColorTheme, NEUTRAL);
+    ENUM_CASE(sync_pb::UserColorTheme, VIBRANT);
+    ENUM_CASE(sync_pb::UserColorTheme, EXPRESSIVE);
+  }
+  NOTREACHED();
+}
+
+const char* ProtoEnumToString(
+    sync_pb::ThemeSpecifics::BrowserColorScheme browser_color_scheme) {
+  ASSERT_ENUM_BOUNDS(sync_pb::ThemeSpecifics, BrowserColorScheme,
+                     BROWSER_COLOR_SCHEME_UNSPECIFIED, DARK);
+  switch (browser_color_scheme) {
+    ENUM_CASE(sync_pb::ThemeSpecifics, BROWSER_COLOR_SCHEME_UNSPECIFIED);
+    ENUM_CASE(sync_pb::ThemeSpecifics, SYSTEM);
+    ENUM_CASE(sync_pb::ThemeSpecifics, LIGHT);
+    ENUM_CASE(sync_pb::ThemeSpecifics, DARK);
+  }
+}
+
+const char* ProtoEnumToString(sync_pb::SharedUrlContext::Source source) {
+  ASSERT_ENUM_BOUNDS(sync_pb::SharedUrlContext, Source, SOURCE_UNSPECIFIED,
+                     CANONICAL_URL);
+  switch (source) {
+    ENUM_CASE(sync_pb::SharedUrlContext, SOURCE_UNSPECIFIED);
+    ENUM_CASE(sync_pb::SharedUrlContext, OMNIBOX);
+    ENUM_CASE(sync_pb::SharedUrlContext, FROM_SYNC);
+    ENUM_CASE(sync_pb::SharedUrlContext, CANONICAL_URL);
+  }
+}
+
+#undef ASSERT_ENUM_BOUNDS
+#undef ENUM_CASE
+
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/proto_enum_conversions.h b/pyhindsight/lib/components/sync/protocol/proto_enum_conversions.h
new file mode 100644
index 0000000..f20e46d
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_enum_conversions.h
@@ -0,0 +1,255 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_PROTO_ENUM_CONVERSIONS_H_
+#define COMPONENTS_SYNC_PROTOCOL_PROTO_ENUM_CONVERSIONS_H_
+
+#include "components/sync/protocol/app_list_specifics.pb.h"
+#include "components/sync/protocol/app_specifics.pb.h"
+#include "components/sync/protocol/autofill_specifics.pb.h"
+#include "components/sync/protocol/contact_info_specifics.pb.h"
+#include "components/sync/protocol/cookie_specifics.pb.h"
+#include "components/sync/protocol/data_type_state.pb.h"
+#include "components/sync/protocol/gaia_password_reuse.pb.h"
+#include "components/sync/protocol/get_updates_caller_info.pb.h"
+#include "components/sync/protocol/nigori_specifics.pb.h"
+#include "components/sync/protocol/note_entity.pb.h"
+#include "components/sync/protocol/power_bookmark_specifics.pb.h"
+#include "components/sync/protocol/proto_value_conversions.h"
+#include "components/sync/protocol/reading_list_specifics.pb.h"
+#include "components/sync/protocol/saved_tab_group_specifics.pb.h"
+#include "components/sync/protocol/session_specifics.pb.h"
+#include "components/sync/protocol/shared_comment_specifics.pb.h"
+#include "components/sync/protocol/shared_tab_group_data_specifics.pb.h"
+#include "components/sync/protocol/sharing_message_specifics.pb.h"
+#include "components/sync/protocol/sync.pb.h"
+#include "components/sync/protocol/sync_enums.pb.h"
+#include "components/sync/protocol/theme_types.pb.h"
+#include "components/sync/protocol/user_consent_types.pb.h"
+#include "components/sync/protocol/user_event_specifics.pb.h"
+#include "components/sync/protocol/web_apk_specifics.pb.h"
+#include "components/sync/protocol/web_app_specifics.pb.h"
+#include "components/sync/protocol/wifi_configuration_specifics.pb.h"
+#include "components/sync/protocol/workspace_desk_specifics.pb.h"
+
+// Keep this file in sync with the .proto files in this directory.
+//
+// Utility functions to get the string equivalent for some sync proto
+// enums.
+
+namespace syncer {
+
+// The returned strings (which don't have to be freed) are in ASCII.
+// The result of passing in an invalid enum value is undefined.
+
+const char* ProtoEnumToString(
+    sync_pb::AppListSpecifics::AppListItemType item_type);
+
+const char* ProtoEnumToString(sync_pb::AppSpecifics::LaunchType launch_type);
+
+const char* ProtoEnumToString(
+    sync_pb::AutofillWalletSpecifics::WalletInfoType wallet_info_type);
+
+const char* ProtoEnumToString(
+    sync_pb::BankAccountDetails::AccountType account_type);
+
+const char* ProtoEnumToString(sync_pb::BookmarkSpecifics::Type type);
+
+const char* ProtoEnumToString(
+    sync_pb::CommitResponse::ResponseType response_type);
+
+const char* ProtoEnumToString(
+    sync_pb::ContactInfoSpecifics::AddressType address_type);
+
+const char* ProtoEnumToString(
+    sync_pb::ContactInfoSpecifics::VerificationStatus verification_status);
+
+const char* ProtoEnumToString(
+    sync_pb::TrustedVaultAutoUpgradeExperimentGroup::Type type);
+
+const char* ProtoEnumToString(sync_pb::NigoriSpecifics::PassphraseType type);
+
+const char* ProtoEnumToString(
+    sync_pb::PaymentInstrument::SupportedRail supported_rail);
+
+const char* ProtoEnumToString(
+    sync_pb::PaymentInstrument::ActionRequired action_required);
+
+const char* ProtoEnumToString(
+    sync_pb::PowerBookmarkSpecifics::PowerType power_type);
+
+const char* ProtoEnumToString(sync_pb::NoteEntity::TargetType target_type);
+
+const char* ProtoEnumToString(
+    sync_pb::ReadingListSpecifics::ReadingListEntryStatus status);
+
+const char* ProtoEnumToString(sync_pb::SavedTabGroup::SavedTabGroupColor color);
+
+const char* ProtoEnumToString(sync_pb::SharedTabGroup::Color color);
+
+const char* ProtoEnumToString(
+    sync_pb::SearchEngineSpecifics::ActiveStatus is_active);
+
+const char* ProtoEnumToString(sync_pb::SessionTab::FaviconType favicon_type);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::BrowserType browser_type);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::Action action);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::DeviceType device_type);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::OsType os_type);
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::DeviceFormFactor device_form_factor);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::ErrorType error_type);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::GetUpdatesOrigin origin);
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::PageTransition page_transition);
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::PageTransitionRedirectType redirect_type);
+
+const char* ProtoEnumToString(
+    sync_pb::SyncEnums::SendTabReceivingType send_tab_receiving_type);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::SingletonDebugEventType type);
+
+const char* ProtoEnumToString(sync_pb::TabNavigation::BlockedState state);
+
+const char* ProtoEnumToString(sync_pb::SyncEnums::PasswordState state);
+
+const char* ProtoEnumToString(sync_pb::UserConsentTypes::ConsentStatus status);
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus::
+        ReportingPopulation safe_browsing_reporting_population);
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction::
+        InteractionResult interaction_result);
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseLookup::LookupResult
+        lookup_result);
+
+const char* ProtoEnumToString(
+    sync_pb::GaiaPasswordReuse::PasswordReuseLookup::ReputationVerdict verdict);
+
+const char* ProtoEnumToString(
+    sync_pb::UserEventSpecifics::GaiaPasswordCaptured::EventTrigger trigger);
+
+const char* ProtoEnumToString(
+    sync_pb::UserEventSpecifics::FlocIdComputed::EventTrigger trigger);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::CardInfoRetrievalEnrollmentState
+        card_info_retrieval_enrollment_state);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::CardBenefitSource
+        card_benefit_source);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::CardCreationSource card_creation_source);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::VirtualCardEnrollmentState
+        virtual_card_enrollment_state);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::VirtualCardEnrollmentType
+        virtual_card_enrollment_type);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::WalletCardStatus wallet_card_status);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMaskedCreditCard::WalletCardType wallet_card_type);
+
+const char* ProtoEnumToString(
+    sync_pb::CardBenefit::CategoryBenefitType category_benefit_type);
+
+const char* ProtoEnumToString(sync_pb::CardIssuer::Issuer issuer);
+
+const char* ProtoEnumToString(
+    sync_pb::WalletMetadataSpecifics::Type wallet_metadata_type);
+
+const char* ProtoEnumToString(sync_pb::WebApkIconInfo::Purpose purpose);
+
+const char* ProtoEnumToString(sync_pb::WebAppIconInfo::Purpose purpose);
+
+const char* ProtoEnumToString(
+    sync_pb::WebAppSpecifics::UserDisplayMode user_display_mode);
+
+const char* ProtoEnumToString(
+    sync_pb::AutofillProfileSpecifics::VerificationStatus status);
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::SecurityType security_type);
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::AutomaticallyConnectOption
+        automatically_connect_option);
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::IsPreferredOption is_preferred_option);
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::MeteredOption metered_option);
+
+const char* ProtoEnumToString(
+    sync_pb::WifiConfigurationSpecifics::ProxyConfiguration::ProxyOption
+        proxy_option);
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::WindowState window_state);
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::LaunchContainer container);
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::WindowOpenDisposition disposition);
+
+const char* ProtoEnumToString(
+    sync_pb::UserConsentTypes::AssistantActivityControlConsent::SettingType
+        setting_type);
+
+const char* ProtoEnumToString(sync_pb::WorkspaceDeskSpecifics::DeskType type);
+
+const char* ProtoEnumToString(
+    sync_pb::WorkspaceDeskSpecifics::TabGroupColor color);
+
+const char* ProtoEnumToString(sync_pb::DataTypeState::InitialSyncState state);
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookieSameSite site_restrictions);
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookiePriority priority);
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookieSourceScheme source_scheme);
+
+const char* ProtoEnumToString(
+    sync_pb::CookieSpecifics::CookieSourceType source_type);
+
+const char* ProtoEnumToString(
+    sync_pb::SharingMessageSpecifics::ChannelConfiguration::
+        ChimeChannelConfiguration::ChimeChannelType channel_type);
+
+const char* ProtoEnumToString(
+    sync_pb::UserColorTheme::BrowserColorVariant browser_color_variant);
+
+const char* ProtoEnumToString(
+    sync_pb::ThemeSpecifics::BrowserColorScheme browser_color_scheme);
+
+const char* ProtoEnumToString(sync_pb::SharedUrlContext::Source source);
+
+}  // namespace syncer
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_PROTO_ENUM_CONVERSIONS_H_
diff --git a/pyhindsight/lib/components/sync/protocol/proto_enum_conversions_unittest.cc b/pyhindsight/lib/components/sync/protocol/proto_enum_conversions_unittest.cc
new file mode 100644
index 0000000..854dda8
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_enum_conversions_unittest.cc
@@ -0,0 +1,159 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/proto_enum_conversions.h"
+
+#include <string>
+
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace syncer {
+namespace {
+
+// WARNING: Keep this file in sync with the .proto files in this directory.
+
+using ::testing::Not;
+using ::testing::StrEq;
+
+// Iterates through the enum values, checking their string version is non-empty.
+// The T##_IsValid() check is needed because some enums have deprecated values,
+// so they have gaps in their numeric range.
+#define TestEnumStringsNonEmpty(T)                                       \
+  for (int i = T##_MIN; i <= T##_MAX; ++i) {                             \
+    if (T##_IsValid(i)) {                                                \
+      EXPECT_THAT(ProtoEnumToString(static_cast<T>(i)), Not(StrEq(""))); \
+    }                                                                    \
+  }
+
+TEST(ProtoEnumConversionsTest, GetAppListItemTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::AppListSpecifics::AppListItemType);
+}
+
+TEST(ProtoEnumConversionsTest, GetBrowserTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::SyncEnums::BrowserType);
+}
+
+TEST(ProtoEnumConversionsTest, GetPageTransitionString) {
+  TestEnumStringsNonEmpty(sync_pb::SyncEnums::PageTransition);
+}
+
+TEST(ProtoEnumConversionsTest, GetPageTransitionQualifierString) {
+  TestEnumStringsNonEmpty(sync_pb::SyncEnums::PageTransitionRedirectType);
+}
+
+TEST(ProtoEnumConversionsTest, GetWifiConfigurationSecurityTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::WifiConfigurationSpecifics::SecurityType);
+}
+
+TEST(ProtoEnumConversionsTest,
+     GetWifiConfigurationAutomaticallyConnectOptionString) {
+  TestEnumStringsNonEmpty(
+      sync_pb::WifiConfigurationSpecifics::AutomaticallyConnectOption);
+}
+
+TEST(ProtoEnumConversionsTest, GetWifiConfigurationIsPreferredOptionString) {
+  TestEnumStringsNonEmpty(
+      sync_pb::WifiConfigurationSpecifics::IsPreferredOption);
+}
+
+TEST(ProtoEnumConversionsTest, GetWifiConfigurationMeteredOptionString) {
+  TestEnumStringsNonEmpty(sync_pb::WifiConfigurationSpecifics::MeteredOption);
+}
+
+TEST(ProtoEnumConversionsTest, GetWifiConfigurationProxyOptionString) {
+  TestEnumStringsNonEmpty(
+      sync_pb::WifiConfigurationSpecifics::ProxyConfiguration::ProxyOption);
+}
+
+TEST(ProtoEnumConversionsTest, GetUpdatesOriginString) {
+  TestEnumStringsNonEmpty(sync_pb::SyncEnums::GetUpdatesOrigin);
+}
+
+TEST(ProtoEnumConversionsTest, GetResponseTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::CommitResponse::ResponseType);
+}
+
+TEST(ProtoEnumConversionsTest, GetErrorTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::SyncEnums::ErrorType);
+}
+
+TEST(ProtoEnumConversionsTest, GetActionString) {
+  TestEnumStringsNonEmpty(sync_pb::SyncEnums::Action);
+}
+
+TEST(ProtoEnumConversionsTest, GetConsentStatusString) {
+  TestEnumStringsNonEmpty(sync_pb::UserConsentTypes::ConsentStatus);
+}
+
+TEST(ProtoEnumConversionsTest, GetVirtualCardEnrollmentTypeString) {
+  TestEnumStringsNonEmpty(
+      sync_pb::WalletMaskedCreditCard::VirtualCardEnrollmentType);
+}
+
+TEST(ProtoEnumConversionsTest, GetSavedTabGroupColorString) {
+  TestEnumStringsNonEmpty(sync_pb::SavedTabGroup::SavedTabGroupColor);
+}
+
+TEST(ProtoEnumConversionsTest, GetSharedTabGroupColorString) {
+  TestEnumStringsNonEmpty(sync_pb::SharedTabGroup::Color);
+}
+
+TEST(ProtoEnumConversionsTest, GetIssuerString) {
+  TestEnumStringsNonEmpty(sync_pb::CardIssuer::Issuer);
+}
+
+TEST(ProtoEnumConversionsTest, GetPowerBookmakrPowerTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::PowerBookmarkSpecifics::PowerType);
+}
+
+TEST(ProtoEnumConversionsTest, GetNoteTargetTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::NoteEntity::TargetType);
+}
+
+TEST(ProtoEnumConversionsTest, GetInitialSyncStateString) {
+  TestEnumStringsNonEmpty(sync_pb::DataTypeState::InitialSyncState);
+}
+
+TEST(ProtoEnumConversionsTest, GetCategoryBenefitTypeString) {
+  TestEnumStringsNonEmpty(sync_pb::CardBenefit::CategoryBenefitType);
+}
+
+TEST(ProtoEnumConversionsTest,
+     GetTrustedVaultAutoUpgradeExperimentGroupTypeString) {
+  TestEnumStringsNonEmpty(
+      sync_pb::TrustedVaultAutoUpgradeExperimentGroup::Type);
+}
+
+TEST(ProtoEnumConversionsTest, GetBrowserColorVariantString) {
+  TestEnumStringsNonEmpty(sync_pb::UserColorTheme::BrowserColorVariant);
+}
+
+TEST(ProtoEnumConversionsTest, GetBrowserColorSchemeString) {
+  TestEnumStringsNonEmpty(sync_pb::ThemeSpecifics::BrowserColorScheme);
+}
+
+TEST(ProtoEnumConversionsTest, GetContactInfoAddressType) {
+  TestEnumStringsNonEmpty(sync_pb::ContactInfoSpecifics::AddressType);
+}
+
+TEST(ProtoEnumConversionsTest, GetCardInfoRetrievalEnrollmentStateString) {
+  TestEnumStringsNonEmpty(
+      sync_pb::WalletMaskedCreditCard::CardInfoRetrievalEnrollmentState);
+}
+
+TEST(ProtoEnumConversionsTest, GetCardBenefitSourceString) {
+  TestEnumStringsNonEmpty(sync_pb::WalletMaskedCreditCard::CardBenefitSource);
+}
+
+TEST(ProtoEnumConversionsTest, GetCardCreationSourceString) {
+  TestEnumStringsNonEmpty(sync_pb::WalletMaskedCreditCard::CardCreationSource);
+}
+
+TEST(ProtoEnumConversionsTest, GetActionRequiredString) {
+  TestEnumStringsNonEmpty(sync_pb::PaymentInstrument::ActionRequired);
+}
+
+}  // namespace
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/proto_memory_estimations.cc b/pyhindsight/lib/components/sync/protocol/proto_memory_estimations.cc
new file mode 100644
index 0000000..a9de71e
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_memory_estimations.cc
@@ -0,0 +1,160 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Keep this file in sync with the .proto files in this directory.
+
+#include "components/sync/protocol/proto_memory_estimations.h"
+
+#include <concepts>
+#include <string>
+
+#include "base/trace_event/memory_usage_estimator.h"
+#include "components/sync/protocol/data_type_progress_marker.pb.h"
+#include "components/sync/protocol/data_type_state.pb.h"
+#include "components/sync/protocol/entity_metadata.pb.h"
+#include "components/sync/protocol/entity_specifics.pb.h"
+#include "components/sync/protocol/nigori_specifics.pb.h"
+#include "components/sync/protocol/persisted_entity_data.pb.h"
+#include "components/sync/protocol/proto_visitors.h"
+#include "components/sync/protocol/sync_entity.pb.h"
+#include "components/sync/protocol/unique_position.pb.h"
+
+namespace {
+
+// This class is a VisitProtoFields()-compatible visitor that estimates
+// proto's memory usage:
+//
+//  MemoryUsageVisitor visitor;
+//  VisitProtoFields(visitor, proto);
+//  size_t memory_usage = visitor.memory_usage();
+//
+class MemoryUsageVisitor {
+ public:
+  MemoryUsageVisitor() = default;
+
+  size_t memory_usage() const { return memory_usage_; }
+
+  template <class P>
+  void VisitBytes(const P& parent_proto,
+                  const char* field_name,
+                  const std::string& field) {
+    // Delegate to Visit(..., const std::string&) below.
+    Visit(parent_proto, field_name, field);
+  }
+
+  template <class P>
+  void VisitBytes(
+      const P& parent_proto,
+      const char* field_name,
+      const google::protobuf::RepeatedPtrField<std::string>& fields) {
+    // Delegate to Visit(..., const std::string&) below.
+    Visit(parent_proto, field_name, fields);
+  }
+
+  template <class P>
+  void VisitSecret(const P& parent_proto,
+                   const char* field_name,
+                   const std::string& field) {
+    // Delegate to Visit(..., const std::string&) below.
+    Visit(parent_proto, field_name, field);
+  }
+
+  template <class P, class E>
+  void VisitEnum(const P&, const char* field_name, E field) {}
+
+  // Types derived from MessageLite (i.e. protos)
+  template <class P, class F>
+    requires(std::derived_from<F, google::protobuf::MessageLite>)
+  void Visit(const P&, const char* field_name, const F& field) {
+    using base::trace_event::EstimateMemoryUsage;
+    // All object fields are dynamically allocated.
+    memory_usage_ += sizeof(F) + EstimateMemoryUsage(field);
+  }
+
+  // Arithmetic types
+  template <class P, class F>
+    requires(std::is_arithmetic_v<F>)
+  void Visit(const P&, const char* field_name, const F& field) {
+    // Arithmetic fields (integers, floats & bool) don't allocate.
+  }
+
+  // std::string
+  template <class P>
+  void Visit(const P&, const char* field_name, const std::string& field) {
+    using base::trace_event::EstimateMemoryUsage;
+    // All strings are of type ArenaStringPtr, which essentially
+    // is std::string*.
+    memory_usage_ += sizeof(std::string) + EstimateMemoryUsage(field);
+  }
+
+  // RepeatedPtrField
+  template <class P, class F>
+  void Visit(const P&,
+             const char* field_name,
+             const google::protobuf::RepeatedPtrField<F>& fields) {
+    using base::trace_event::EstimateMemoryUsage;
+    // Can't use RepeatedPtrField::SpaceUsedExcludingSelf() because it will
+    // end up calling undefined TypeHandler::SpaceUsed() method.
+    memory_usage_ += fields.Capacity() ? sizeof(void*) : 0;  // header
+    memory_usage_ += fields.Capacity() * sizeof(void*);
+    for (const auto& field : fields) {
+      memory_usage_ += sizeof(F) + EstimateMemoryUsage(field);
+    }
+  }
+
+  // RepeatedField<arithmetic type>
+  template <class P, class F>
+    requires(std::is_arithmetic_v<F>)
+  void Visit(const P&,
+             const char* field_name,
+             const google::protobuf::RepeatedField<F>& fields) {
+    memory_usage_ += fields.SpaceUsedExcludingSelf();
+    // Arithmetic fields (integers, floats & bool) don't allocate, so no point
+    // in iterating over `fields`.
+  }
+
+  // RepeatedField<std::string>
+  template <class P>
+  void Visit(const P&,
+             const char* field_name,
+             const google::protobuf::RepeatedField<std::string>& fields) {
+    using base::trace_event::EstimateMemoryUsage;
+    memory_usage_ += fields.SpaceUsedExcludingSelf();
+    for (const auto& field : fields) {
+      memory_usage_ += EstimateMemoryUsage(field);
+    }
+  }
+
+ private:
+  size_t memory_usage_ = 0;
+};
+
+}  // namespace
+
+namespace sync_pb {
+
+template <class P>
+size_t EstimateMemoryUsage(const P& proto) {
+  MemoryUsageVisitor visitor;
+  syncer::VisitProtoFields(visitor, proto);
+  return visitor.memory_usage();
+}
+
+// Explicit instantiations
+
+#define INSTANTIATE(Proto) \
+  template size_t EstimateMemoryUsage<Proto>(const Proto&);
+
+INSTANTIATE(CrossUserSharingPublicKey)
+INSTANTIATE(DataTypeContext)
+INSTANTIATE(DataTypeProgressMarker)
+INSTANTIATE(DataTypeState)
+INSTANTIATE(DeletionOrigin)
+INSTANTIATE(EntityMetadata)
+INSTANTIATE(EntitySpecifics)
+INSTANTIATE(PersistedEntityData)
+INSTANTIATE(SyncEntity)
+INSTANTIATE(UniquePosition)
+
+}  // namespace sync_pb
diff --git a/pyhindsight/lib/components/sync/protocol/proto_memory_estimations.h b/pyhindsight/lib/components/sync/protocol/proto_memory_estimations.h
new file mode 100644
index 0000000..26d3123
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_memory_estimations.h
@@ -0,0 +1,22 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_PROTO_MEMORY_ESTIMATIONS_H_
+#define COMPONENTS_SYNC_PROTOCOL_PROTO_MEMORY_ESTIMATIONS_H_
+
+#include <stddef.h>
+
+namespace sync_pb {
+
+// Estimates memory usage for a proto.
+// Needs to be in sync_pb namespace for ADL to find it (when for example
+// EstimateMemoryUsage() is called on a list of protos).
+// Note: if you get linking errors you need to add explicit instantiation at
+// the end of the implementation file.
+template <class P>
+size_t EstimateMemoryUsage(const P& proto);
+
+}  // namespace sync_pb
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_PROTO_MEMORY_ESTIMATIONS_H_
diff --git a/pyhindsight/lib/components/sync/protocol/proto_value_conversions.cc b/pyhindsight/lib/components/sync/protocol/proto_value_conversions.cc
new file mode 100644
index 0000000..7452bfc
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_value_conversions.cc
@@ -0,0 +1,430 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/proto_value_conversions.h"
+
+#include <stdint.h>
+
+#include <string>
+#include <utility>
+
+#include "base/base64.h"
+#include "base/memory/raw_ptr.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/stringprintf.h"
+#include "base/values.h"
+#include "components/sync/base/unique_position.h"
+#include "components/sync/protocol/app_list_specifics.pb.h"
+#include "components/sync/protocol/app_setting_specifics.pb.h"
+#include "components/sync/protocol/app_specifics.pb.h"
+#include "components/sync/protocol/arc_package_specifics.pb.h"
+#include "components/sync/protocol/autofill_offer_specifics.pb.h"
+#include "components/sync/protocol/autofill_specifics.pb.h"
+#include "components/sync/protocol/bookmark_specifics.pb.h"
+#include "components/sync/protocol/collaboration_group_specifics.pb.h"
+#include "components/sync/protocol/contact_info_specifics.pb.h"
+#include "components/sync/protocol/cookie_specifics.pb.h"
+#include "components/sync/protocol/data_type_progress_marker.pb.h"
+#include "components/sync/protocol/dictionary_specifics.pb.h"
+#include "components/sync/protocol/entity_specifics.pb.h"
+#include "components/sync/protocol/extension_setting_specifics.pb.h"
+#include "components/sync/protocol/extension_specifics.pb.h"
+#include "components/sync/protocol/history_delete_directive_specifics.pb.h"
+#include "components/sync/protocol/history_specifics.pb.h"
+#include "components/sync/protocol/nigori_specifics.pb.h"
+#include "components/sync/protocol/os_preference_specifics.pb.h"
+#include "components/sync/protocol/os_priority_preference_specifics.pb.h"
+#include "components/sync/protocol/password_sharing_invitation_specifics.pb.h"
+#include "components/sync/protocol/password_specifics.pb.h"
+#include "components/sync/protocol/plus_address_setting_specifics.pb.h"
+#include "components/sync/protocol/plus_address_specifics.pb.h"
+#include "components/sync/protocol/preference_specifics.pb.h"
+#include "components/sync/protocol/printer_specifics.pb.h"
+#include "components/sync/protocol/printers_authorization_server_specifics.pb.h"
+#include "components/sync/protocol/priority_preference_specifics.pb.h"
+#include "components/sync/protocol/product_comparison_specifics.pb.h"
+#include "components/sync/protocol/proto_visitors.h"
+#include "components/sync/protocol/reading_list_specifics.pb.h"
+#include "components/sync/protocol/saved_tab_group_specifics.pb.h"
+#include "components/sync/protocol/search_engine_specifics.pb.h"
+#include "components/sync/protocol/send_tab_to_self_specifics.pb.h"
+#include "components/sync/protocol/session_specifics.pb.h"
+#include "components/sync/protocol/shared_comment_specifics.pb.h"
+#include "components/sync/protocol/sharing_message_specifics.pb.h"
+#include "components/sync/protocol/sync.pb.h"
+#include "components/sync/protocol/sync_entity.pb.h"
+#include "components/sync/protocol/theme_specifics.pb.h"
+#include "components/sync/protocol/typed_url_specifics.pb.h"
+#include "components/sync/protocol/user_consent_specifics.pb.h"
+#include "components/sync/protocol/user_event_specifics.pb.h"
+#include "components/sync/protocol/web_apk_specifics.pb.h"
+#include "components/sync/protocol/web_app_specifics.pb.h"
+#include "components/sync/protocol/webauthn_credential_specifics.pb.h"
+#include "components/sync/protocol/workspace_desk_specifics.pb.h"
+
+namespace syncer {
+
+namespace {
+
+// ToValueVisitor is a VisitProtoFields()-compatible visitor that serializes
+// protos to base::Value. To serialize a proto you call ToValue() method:
+//
+//  ToValueVisitor visitor;
+//  auto value = visitor.ToValue(proto);
+//
+// By default all fields visited by VisitProtoFields() are serialized, but
+// there are several ways to customize that on per-field / per-proto basis:
+//
+// 1. If you want to change how fields of a particular proto type are
+//    serialized, customize Visit() method:
+//
+//    template <class P, class F>
+//    void Visit(const P& parent_proto,
+//               const char* field_name, const F& field);
+//
+//    By default Visit() serializes `field` and sets it to `value_` under
+//    `field_name` name. Default implementation is accessible via VisitImpl().
+//
+//    For example here is how you would serialize only GreenProto::content
+//    for all GreenProto fields:
+//
+//    template <class P>
+//    void Visit(const P& parent_proto,
+//               const char* field_name, const sync_pb::GreenProto& field) {
+//      if (field.has_content()) {
+//        value_->Set(field_name, field.content());
+//      }
+//    }
+//
+//    You can further fine-tune this method by specifying parent proto. For
+//    example let's say we don't want to serialize fields of type GreenProto
+//    that are contained in RedProto:
+//
+//    void Visit(const sync_pb::RedProto& parent_proto,
+//               const char* field_name, const sync_pb::GreenProto& field) {}
+//
+//    Note: Visit() method only called to serialize fields, and doesn't
+//    affect top level protos. I.e. ToValueVisitor().ToValue(GreenProto)
+//    won't call methods above.
+//
+// 2. If you want to change how proto itself is serialized, you need to
+//    customize ToValue() method:
+//
+//    template <class P>
+//    base::Value ToValue(const P& proto) const;
+//
+//    By default ToValue() creates new instance of ToValueVisitor, calls
+//    VisitProtoFields(visitor, `proto`) and returns visitor's `value_`.
+//    Default implementation is accessible via ToValueDictImpl().
+//
+//    For example let's say you want to clobber a sensitive field:
+//
+//    base::Value ToValue(const sync_pb::GreenProto& proto) const {
+//      base::Value::Dict value = ToValueDictImpl(proto);
+//      value.Set("secret", "<clobbered>");
+//      return base::Value(value);
+//    }
+//
+//    ToValue() doesn't have to return a dictionary though. It might
+//    be more appropriate to serialize GreenProto into a string instead:
+//
+//    base::Value ToValue(const sync_pb::GreenProto& proto) const {
+//      return base::Value(proto.content());
+//    }
+//
+class ToValueVisitor {
+ public:
+  explicit ToValueVisitor(const ProtoValueConversionOptions& options =
+                              ProtoValueConversionOptions(),
+                          base::Value::Dict* value = nullptr)
+      : options_(options), value_(value) {}
+
+  template <class P>
+  void VisitBytes(const P& parent_proto,
+                  const char* field_name,
+                  const std::string& field) {
+    value_->Set(field_name,
+                base::Base64Encode(base::as_bytes(base::span(field))));
+  }
+
+  template <class P>
+  void VisitBytes(
+      const P& parent_proto,
+      const char* field_name,
+      const google::protobuf::RepeatedPtrField<std::string>& repeated_field) {
+    if (!repeated_field.empty()) {
+      base::Value::List list;
+      for (const auto& field : repeated_field) {
+        list.Append(base::Base64Encode(base::as_byte_span(field)));
+      }
+      value_->Set(field_name, std::move(list));
+    }
+  }
+
+  template <class P>
+  void VisitSecret(const P& parent_proto,
+                   const char* field_name,
+                   const std::string& field) {
+    value_->Set(field_name,
+                base::StringPrintf("<%zu-byte secret>", field.size()));
+  }
+
+  template <class P, class E>
+  void VisitEnum(const P& parent_proto, const char* field_name, E field) {
+    value_->Set(field_name, ProtoEnumToString(field));
+  }
+
+  template <class P, class F>
+  void Visit(const P& parent_proto,
+             const char* field_name,
+             const google::protobuf::RepeatedPtrField<F>& repeated_field) {
+    if (!repeated_field.empty()) {
+      base::Value::List list;
+      for (const auto& field : repeated_field) {
+        list.Append(ToValue(field));
+      }
+      value_->Set(field_name, std::move(list));
+    }
+  }
+
+  template <class P, class F>
+  void Visit(const P& parent_proto,
+             const char* field_name,
+             const google::protobuf::RepeatedField<F>& repeated_field) {
+    if (!repeated_field.empty()) {
+      base::Value::List list;
+      for (const auto& field : repeated_field) {
+        list.Append(ToValue(field));
+      }
+      value_->Set(field_name, std::move(list));
+    }
+  }
+
+  template <class P, class F>
+  void Visit(const P& parent_proto, const char* field_name, const F& field) {
+    VisitImpl(parent_proto, field_name, field);
+  }
+
+  template <class P>
+  base::Value ToValue(const P& proto) const {
+    return base::Value(ToValueDictImpl(proto));
+  }
+
+  // Customizations
+
+  // EntitySpecifics
+  template <class P>
+  void Visit(const P& parent_proto,
+             const char* field_name,
+             const sync_pb::EntitySpecifics& field) {
+    if (options_.include_specifics) {
+      VisitImpl(parent_proto, field_name, field);
+    }
+  }
+
+  // GetUpdateTriggers.
+  base::Value ToValue(const sync_pb::GetUpdateTriggers& proto) const {
+    base::Value::Dict dict = ToValueDictImpl(proto);
+    if (!options_.include_full_get_update_triggers) {
+      if (!proto.client_dropped_hints()) {
+        dict.Remove("client_dropped_hints");
+      }
+      if (!proto.invalidations_out_of_sync()) {
+        dict.Remove("invalidations_out_of_sync");
+      }
+      if (proto.local_modification_nudges() == 0) {
+        dict.Remove("local_modification_nudges");
+      }
+      if (proto.datatype_refresh_nudges() == 0) {
+        dict.Remove("datatype_refresh_nudges");
+      }
+      if (!proto.server_dropped_hints()) {
+        dict.Remove("server_dropped_hints");
+      }
+      if (!proto.initial_sync_in_progress()) {
+        dict.Remove("initial_sync_in_progress");
+      }
+      if (!proto.sync_for_resolve_conflict_in_progress()) {
+        dict.Remove("sync_for_resolve_conflict_in_progress");
+      }
+    }
+    return base::Value(std::move(dict));
+  }
+
+  // AutofillWalletSpecifics
+  base::Value ToValue(const sync_pb::AutofillWalletSpecifics& proto) const {
+    base::Value::Dict dict = ToValueDictImpl(proto);
+    // TODO(crbug.com/40252694): consider whether the VISIT_SECRET macro in
+    // proto_visitors.h could replace this.
+    if (proto.type() != sync_pb::AutofillWalletSpecifics::POSTAL_ADDRESS) {
+      dict.Remove("address");
+    }
+    if (proto.type() != sync_pb::AutofillWalletSpecifics::MASKED_CREDIT_CARD) {
+      dict.Remove("masked_card");
+    }
+    if (proto.type() != sync_pb::AutofillWalletSpecifics::CUSTOMER_DATA) {
+      dict.Remove("customer_data");
+    }
+    if (proto.type() !=
+        sync_pb::AutofillWalletSpecifics::CREDIT_CARD_CLOUD_TOKEN_DATA) {
+      dict.Remove("cloud_token_data");
+    }
+    if (proto.type() != sync_pb::AutofillWalletSpecifics::PAYMENT_INSTRUMENT) {
+      dict.Remove("payment_instrument");
+    }
+    return base::Value(std::move(dict));
+  }
+
+  // UniquePosition
+  base::Value ToValue(const sync_pb::UniquePosition& proto) const {
+    UniquePosition pos = UniquePosition::FromProto(proto);
+    return base::Value(pos.ToDebugString());
+  }
+
+ private:
+  template <class P>
+  base::Value::Dict ToValueDictImpl(const P& proto) const {
+    base::Value::Dict dict;
+    ToValueVisitor visitor(options_, &dict);
+    VisitProtoFields(visitor, proto);
+    return dict;
+  }
+
+  base::Value ToValue(const std::string& value) const {
+    return base::Value(value);
+  }
+
+  base::Value ToValue(int64_t value) const {
+    return base::Value(base::NumberToString(value));
+  }
+  base::Value ToValue(uint64_t value) const {
+    return base::Value(base::NumberToString(value));
+  }
+  base::Value ToValue(uint32_t value) const {
+    return base::Value(base::NumberToString(value));
+  }
+  base::Value ToValue(int32_t value) const {
+    return base::Value(base::NumberToString(value));
+  }
+
+  base::Value ToValue(bool value) const { return base::Value(value); }
+  base::Value ToValue(float value) const { return base::Value(value); }
+  base::Value ToValue(double value) const { return base::Value(value); }
+
+  // Needs to be here to see all ToValue() overloads above.
+  template <class P, class F>
+  void VisitImpl(P&, const char* field_name, const F& field) {
+    value_->Set(field_name, ToValue(field));
+  }
+
+  const ProtoValueConversionOptions options_;
+  const raw_ptr<base::Value::Dict> value_;
+};
+
+}  // namespace
+
+#define IMPLEMENT_PROTO_TO_VALUE(Proto)                     \
+  base::Value Proto##ToValue(const sync_pb::Proto& proto) { \
+    return ToValueVisitor().ToValue(proto);                 \
+  }
+
+#define IMPLEMENT_PROTO_TO_VALUE_WITH_OPTIONS(Proto)                       \
+  base::Value Proto##ToValue(const sync_pb::Proto& proto,                  \
+                             const ProtoValueConversionOptions& options) { \
+    return ToValueVisitor(options).ToValue(proto);                         \
+  }
+
+IMPLEMENT_PROTO_TO_VALUE(AppListSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AppSettingSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AppSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(ArcPackageSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AutofillOfferSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AutofillProfileSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AutofillSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AutofillWalletCredentialSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AutofillWalletSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(AutofillWalletUsageSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(BankAccountDetails)
+IMPLEMENT_PROTO_TO_VALUE(BookmarkSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(ClientConfigParams)
+IMPLEMENT_PROTO_TO_VALUE(CollaborationGroupSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(ContactInfoSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(CookieSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(CrossUserSharingPublicKey)
+IMPLEMENT_PROTO_TO_VALUE(DebugEventInfo)
+IMPLEMENT_PROTO_TO_VALUE(DebugInfo)
+IMPLEMENT_PROTO_TO_VALUE(DeviceDetails)
+IMPLEMENT_PROTO_TO_VALUE(DeviceInfoSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(DictionarySpecifics)
+IMPLEMENT_PROTO_TO_VALUE(EncryptedData)
+IMPLEMENT_PROTO_TO_VALUE(EntityMetadata)
+IMPLEMENT_PROTO_TO_VALUE(EntitySpecifics)
+IMPLEMENT_PROTO_TO_VALUE(EwalletDetails)
+IMPLEMENT_PROTO_TO_VALUE(ExtensionSettingSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(ExtensionSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(GlobalIdDirective)
+IMPLEMENT_PROTO_TO_VALUE(HistoryDeleteDirectiveSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(HistorySpecifics)
+IMPLEMENT_PROTO_TO_VALUE(IncomingPasswordSharingInvitationSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(LinkedAppIconInfo)
+IMPLEMENT_PROTO_TO_VALUE(ManagedUserSettingSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(NavigationRedirect)
+IMPLEMENT_PROTO_TO_VALUE(NigoriSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(OsPreferenceSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(OsPriorityPreferenceSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(OutgoingPasswordSharingInvitationSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PasswordSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PasswordSpecificsData)
+IMPLEMENT_PROTO_TO_VALUE(PasswordSpecificsData_Notes)
+IMPLEMENT_PROTO_TO_VALUE(PasswordSpecificsData_Notes_Note)
+IMPLEMENT_PROTO_TO_VALUE(PaymentInstrument)
+IMPLEMENT_PROTO_TO_VALUE(PaymentsCustomerData)
+IMPLEMENT_PROTO_TO_VALUE(PlusAddressSettingSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PlusAddressSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PowerBookmarkSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PreferenceSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PrinterPPDReference)
+IMPLEMENT_PROTO_TO_VALUE(PrinterSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PrintersAuthorizationServerSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(PriorityPreferenceSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(ProductComparisonSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(ReadingListSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SavedTabGroupSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SearchEngineSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SecurityEventSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SendTabToSelfPush)
+IMPLEMENT_PROTO_TO_VALUE(SendTabToSelfSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SessionHeader)
+IMPLEMENT_PROTO_TO_VALUE(SessionSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SessionTab)
+IMPLEMENT_PROTO_TO_VALUE(SessionWindow)
+IMPLEMENT_PROTO_TO_VALUE(SharedCommentSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SharingMessageSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(SyncCycleCompletedEventInfo)
+IMPLEMENT_PROTO_TO_VALUE(TabNavigation)
+IMPLEMENT_PROTO_TO_VALUE(ThemeSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(TimeRangeDirective)
+IMPLEMENT_PROTO_TO_VALUE(TypedUrlSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(UnencryptedSharingMessage)
+IMPLEMENT_PROTO_TO_VALUE(UrlDirective)
+IMPLEMENT_PROTO_TO_VALUE(UserConsentSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(UserEventSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(WalletCreditCardCloudTokenData)
+IMPLEMENT_PROTO_TO_VALUE(WalletMaskedCreditCard)
+IMPLEMENT_PROTO_TO_VALUE(WalletMetadataSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(WalletPostalAddress)
+IMPLEMENT_PROTO_TO_VALUE(WebApkSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(WebAppSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(WebauthnCredentialSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(WifiConfigurationSpecifics)
+IMPLEMENT_PROTO_TO_VALUE(WorkspaceDeskSpecifics)
+
+IMPLEMENT_PROTO_TO_VALUE_WITH_OPTIONS(ClientToServerMessage)
+IMPLEMENT_PROTO_TO_VALUE_WITH_OPTIONS(ClientToServerResponse)
+IMPLEMENT_PROTO_TO_VALUE_WITH_OPTIONS(SyncEntity)
+
+#undef IMPLEMENT_PROTO_TO_VALUE
+#undef IMPLEMENT_PROTO_TO_VALUE_WITH_OPTIONS
+
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/proto_value_conversions.h b/pyhindsight/lib/components/sync/protocol/proto_value_conversions.h
new file mode 100644
index 0000000..cdc362b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_value_conversions.h
@@ -0,0 +1,360 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_PROTO_VALUE_CONVERSIONS_H_
+#define COMPONENTS_SYNC_PROTOCOL_PROTO_VALUE_CONVERSIONS_H_
+
+namespace base {
+class Value;
+}
+
+namespace sync_pb {
+class AppListSpecifics;
+class AppSettingSpecifics;
+class AppSpecifics;
+class ArcPackageSpecifics;
+class AutofillProfileSpecifics;
+class AutofillSpecifics;
+class AutofillOfferSpecifics;
+class AutofillWalletCredentialSpecifics;
+class AutofillWalletSpecifics;
+class AutofillWalletUsageSpecifics;
+class BankAccountDetails;
+class BookmarkSpecifics;
+class ClientConfigParams;
+class ClientToServerMessage;
+class ClientToServerResponse;
+class CollaborationGroupSpecifics;
+class ContactInfoSpecifics;
+class CookieSpecifics;
+class CrossUserSharingPublicKey;
+class DebugEventInfo;
+class DebugInfo;
+class DeviceDetails;
+class DeviceInfoSpecifics;
+class DictionarySpecifics;
+class EncryptedData;
+class EntityMetadata;
+class EntitySpecifics;
+class EwalletDetails;
+class ExtensionSettingSpecifics;
+class ExtensionSpecifics;
+class HistoryDeleteDirectiveSpecifics;
+class HistorySpecifics;
+class IncomingPasswordSharingInvitationSpecifics;
+class LinkedAppIconInfo;
+class ManagedUserSettingSpecifics;
+class NavigationRedirect;
+class NigoriSpecifics;
+class OsPreferenceSpecifics;
+class OsPriorityPreferenceSpecifics;
+class OutgoingPasswordSharingInvitationSpecifics;
+class PasswordSpecifics;
+class PasswordSpecificsData;
+class PaymentInstrument;
+class PaymentsCustomerData;
+class PlusAddressSettingSpecifics;
+class PlusAddressSpecifics;
+class PowerBookmarkSpecifics;
+class PreferenceSpecifics;
+class PrinterPPDReference;
+class PrinterSpecifics;
+class PrintersAuthorizationServerSpecifics;
+class PriorityPreferenceSpecifics;
+class ProductComparisonSpecifics;
+class ReadingListSpecifics;
+class SavedTabGroupSpecifics;
+class SearchEngineSpecifics;
+class SecurityEventSpecifics;
+class SendTabToSelfPush;
+class SendTabToSelfSpecifics;
+class SessionHeader;
+class SessionSpecifics;
+class SessionTab;
+class SessionWindow;
+class SharingMessageSpecifics;
+class SyncCycleCompletedEventInfo;
+class SyncEntity;
+class TabNavigation;
+class ThemeSpecifics;
+class TimeRangeDirective;
+class TypedUrlSpecifics;
+class UnencryptedSharingMessage;
+class UrlDirective;
+class UserConsentSpecifics;
+class UserEventSpecifics;
+class WalletCreditCardCloudTokenData;
+class WalletMaskedCreditCard;
+class WalletMetadataSpecifics;
+class WalletPostalAddress;
+class WebApkSpecifics;
+class WebAppSpecifics;
+class WebauthnCredentialSpecifics;
+class WifiConfigurationSpecifics;
+class WorkspaceDeskSpecifics;
+}  // namespace sync_pb
+
+// Keep this file in sync with the .proto files in this directory.
+//
+// Utility functions to convert sync protocol buffers to dictionaries.
+// Each protocol field is mapped to a key of the same name.  Repeated
+// fields are mapped to array values and sub-messages are mapped to
+// sub-dictionary values.
+
+namespace syncer {
+
+base::Value AppListSpecificsToValue(const sync_pb::AppListSpecifics& proto);
+
+base::Value AppSettingSpecificsToValue(
+    const sync_pb::AppSettingSpecifics& app_setting_specifics);
+
+base::Value AppSpecificsToValue(const sync_pb::AppSpecifics& app_specifics);
+
+base::Value ArcPackageSpecificsToValue(
+    const sync_pb::ArcPackageSpecifics& proto);
+
+base::Value AutofillOfferSpecificsToValue(
+    const sync_pb::AutofillOfferSpecifics& autofill_offer_specifics);
+
+base::Value AutofillProfileSpecificsToValue(
+    const sync_pb::AutofillProfileSpecifics& autofill_profile_specifics);
+
+base::Value AutofillSpecificsToValue(
+    const sync_pb::AutofillSpecifics& autofill_specifics);
+
+base::Value AutofillWalletCredentialSpecificsToValue(
+    const sync_pb::AutofillWalletCredentialSpecifics&
+        autofill_wallet_credential_specifics);
+
+base::Value AutofillWalletSpecificsToValue(
+    const sync_pb::AutofillWalletSpecifics& autofill_wallet_specifics);
+
+base::Value AutofillWalletUsageSpecificsToValue(
+    const sync_pb::AutofillWalletUsageSpecifics&
+        autofill_wallet_usage_specifics);
+
+base::Value BankAccountDetailsToValue(
+    const sync_pb::BankAccountDetails& bank_account_details);
+
+base::Value BookmarkSpecificsToValue(
+    const sync_pb::BookmarkSpecifics& bookmark_specifics);
+
+base::Value ClientConfigParamsToValue(const sync_pb::ClientConfigParams& proto);
+
+base::Value CollaborationGroupSpecificsToValue(
+    const sync_pb::CollaborationGroupSpecifics& proto);
+
+base::Value ContactInfoSpecificsToValue(
+    const sync_pb::ContactInfoSpecifics& proto);
+
+base::Value CookieSpecificsToValue(const sync_pb::CookieSpecifics& proto);
+
+base::Value DebugEventInfoToValue(const sync_pb::DebugEventInfo& proto);
+
+base::Value DebugInfoToValue(const sync_pb::DebugInfo& proto);
+
+base::Value DeviceDetailsToValue(const sync_pb::DeviceDetails& device_details);
+
+base::Value DeviceInfoSpecificsToValue(
+    const sync_pb::DeviceInfoSpecifics& device_info_specifics);
+
+base::Value DictionarySpecificsToValue(
+    const sync_pb::DictionarySpecifics& dictionary_specifics);
+
+base::Value EncryptedDataToValue(const sync_pb::EncryptedData& encrypted_data);
+
+base::Value EntityMetadataToValue(const sync_pb::EntityMetadata& metadata);
+
+base::Value EntitySpecificsToValue(const sync_pb::EntitySpecifics& specifics);
+
+base::Value EwalletDetailsToValue(
+    const sync_pb::EwalletDetails& ewallet_details);
+
+base::Value ExtensionSettingSpecificsToValue(
+    const sync_pb::ExtensionSettingSpecifics& extension_setting_specifics);
+
+base::Value ExtensionSpecificsToValue(
+    const sync_pb::ExtensionSpecifics& extension_specifics);
+
+base::Value HistoryDeleteDirectiveSpecificsToValue(
+    const sync_pb::HistoryDeleteDirectiveSpecifics&
+        history_delete_directive_specifics);
+
+base::Value HistorySpecificsToValue(
+    const sync_pb::HistorySpecifics& history_specifics);
+
+base::Value IncomingPasswordSharingInvitationSpecificsToValue(
+    const sync_pb::IncomingPasswordSharingInvitationSpecifics& specifics);
+
+base::Value LinkedAppIconInfoToValue(
+    const sync_pb::LinkedAppIconInfo& linked_app_icon_info);
+
+base::Value ManagedUserSettingSpecificsToValue(
+    const sync_pb::ManagedUserSettingSpecifics& managed_user_setting_specifics);
+
+base::Value NavigationRedirectToValue(
+    const sync_pb::NavigationRedirect& navigation_redirect);
+
+base::Value NigoriSpecificsToValue(
+    const sync_pb::NigoriSpecifics& nigori_specifics);
+
+base::Value OsPreferenceSpecificsToValue(
+    const sync_pb::OsPreferenceSpecifics& specifics);
+
+base::Value OsPriorityPreferenceSpecificsToValue(
+    const sync_pb::OsPriorityPreferenceSpecifics& specifics);
+
+base::Value OutgoingPasswordSharingInvitationSpecificsToValue(
+    const sync_pb::OutgoingPasswordSharingInvitationSpecifics& specifics);
+
+base::Value PasswordSpecificsToValue(
+    const sync_pb::PasswordSpecifics& password_specifics);
+
+base::Value PasswordSpecificsDataToValue(
+    const sync_pb::PasswordSpecificsData& password_specifics_data);
+
+base::Value PaymentInstrumentToValue(
+    const sync_pb::PaymentInstrument& payment_instrument);
+
+base::Value PaymentsCustomerDataToValue(
+    const sync_pb::PaymentsCustomerData& payments_customer_data);
+
+base::Value PlusAddressSettingSpecificsToValue(
+    const sync_pb::PlusAddressSettingSpecifics& plus_address_setting_specifics);
+
+base::Value PlusAddressSpecificsToValue(
+    const sync_pb::PlusAddressSpecifics& plus_address_specifics);
+
+base::Value PowerBookmarkSpecificsToValue(
+    const sync_pb::PowerBookmarkSpecifics& power_bookmark_specifics);
+
+base::Value PreferenceSpecificsToValue(
+    const sync_pb::PreferenceSpecifics& password_specifics);
+
+base::Value PrinterPPDReferenceToValue(
+    const sync_pb::PrinterPPDReference& proto);
+
+base::Value PrinterSpecificsToValue(
+    const sync_pb::PrinterSpecifics& printer_specifics);
+
+base::Value PrintersAuthorizationServerSpecificsToValue(
+    const sync_pb::PrintersAuthorizationServerSpecifics&
+        printers_authorization_server_specifics);
+
+base::Value PriorityPreferenceSpecificsToValue(
+    const sync_pb::PriorityPreferenceSpecifics& proto);
+
+base::Value ProductComparisonSpecificsToValue(
+    const sync_pb::ProductComparisonSpecifics& product_comparison_specifics);
+
+base::Value CrossUserSharingPublicKeyToValue(
+    const sync_pb::CrossUserSharingPublicKey& proto);
+
+base::Value ReadingListSpecificsToValue(
+    const sync_pb::ReadingListSpecifics& proto);
+
+base::Value SavedTabGroupSpecificsToValue(
+    const sync_pb::SavedTabGroupSpecifics& saved_tab_group_specifics);
+
+base::Value SearchEngineSpecificsToValue(
+    const sync_pb::SearchEngineSpecifics& search_engine_specifics);
+
+base::Value SendTabToSelfPushToValue(
+    const sync_pb::SendTabToSelfPush& send_tab_push);
+
+base::Value SendTabToSelfSpecificsToValue(
+    const sync_pb::SendTabToSelfSpecifics& send_tab_specifics);
+
+base::Value SecurityEventSpecificsToValue(
+    const sync_pb::SecurityEventSpecifics& security_event_specifics);
+
+base::Value SessionHeaderToValue(const sync_pb::SessionHeader& session_header);
+
+base::Value SessionSpecificsToValue(
+    const sync_pb::SessionSpecifics& session_specifics);
+
+base::Value SessionTabToValue(const sync_pb::SessionTab& session_tab);
+
+base::Value SessionWindowToValue(const sync_pb::SessionWindow& session_window);
+
+base::Value SharingMessageSpecificsToValue(
+    const sync_pb::SharingMessageSpecifics& sharing_message_specifics);
+
+base::Value SyncCycleCompletedEventInfoToValue(
+    const sync_pb::SyncCycleCompletedEventInfo& proto);
+
+base::Value TabNavigationToValue(const sync_pb::TabNavigation& tab_navigation);
+
+base::Value ThemeSpecificsToValue(
+    const sync_pb::ThemeSpecifics& theme_specifics);
+
+base::Value TimeRangeDirectiveToValue(
+    const sync_pb::TimeRangeDirective& time_range_directive);
+
+base::Value TypedUrlSpecificsToValue(
+    const sync_pb::TypedUrlSpecifics& typed_url_specifics);
+
+base::Value UnencryptedSharingMessageToValue(
+    const sync_pb::UnencryptedSharingMessage& proto);
+
+base::Value UrlDirectiveToValue(
+    const sync_pb::UrlDirective& time_range_directive);
+
+base::Value UserConsentSpecificsToValue(
+    const sync_pb::UserConsentSpecifics& user_consent_specifics);
+
+base::Value UserEventSpecificsToValue(
+    const sync_pb::UserEventSpecifics& user_event_specifics);
+
+base::Value WalletCreditCardCloudTokenDataToValue(
+    const sync_pb::WalletCreditCardCloudTokenData& cloud_token_data);
+
+base::Value WalletMaskedCreditCardToValue(
+    const sync_pb::WalletMaskedCreditCard& wallet_masked_card);
+
+base::Value WalletMetadataSpecificsToValue(
+    const sync_pb::WalletMetadataSpecifics& wallet_metadata_specifics);
+
+base::Value WalletPostalAddressToValue(
+    const sync_pb::WalletPostalAddress& wallet_postal_address);
+
+base::Value WebApkSpecificsToValue(
+    const sync_pb::WebApkSpecifics& web_apk_specifics);
+
+base::Value WebAppSpecificsToValue(
+    const sync_pb::WebAppSpecifics& web_app_specifics);
+
+base::Value WebAuthnCredentialSpecificsToValue(
+    const sync_pb::WebauthnCredentialSpecifics& webauthn_credential_specifics);
+
+base::Value WifiConfigurationSpecificsToValue(
+    const sync_pb::WifiConfigurationSpecifics& wifi_configuration_specifics);
+
+base::Value WorkspaceDeskSpecificsToValue(
+    const sync_pb::WorkspaceDeskSpecifics& workspace_desk_specifics);
+
+// ToValue functions that allow omitting specifics and other fields.
+
+struct ProtoValueConversionOptions {
+  // Whether to include specifics.
+  bool include_specifics = true;
+
+  // Whether to include default values which are set in GetUpdateTriggers.
+  bool include_full_get_update_triggers = true;
+};
+
+base::Value ClientToServerMessageToValue(
+    const sync_pb::ClientToServerMessage& proto,
+    const ProtoValueConversionOptions& options);
+
+base::Value ClientToServerResponseToValue(
+    const sync_pb::ClientToServerResponse& proto,
+    const ProtoValueConversionOptions& options);
+
+base::Value SyncEntityToValue(const sync_pb::SyncEntity& entity,
+                              const ProtoValueConversionOptions& options);
+
+}  // namespace syncer
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_PROTO_VALUE_CONVERSIONS_H_
diff --git a/pyhindsight/lib/components/sync/protocol/proto_value_conversions_unittest.cc b/pyhindsight/lib/components/sync/protocol/proto_value_conversions_unittest.cc
new file mode 100644
index 0000000..3333391
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_value_conversions_unittest.cc
@@ -0,0 +1,397 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/proto_value_conversions.h"
+
+#include <memory>
+#include <string>
+#include <utility>
+
+#include "base/strings/string_number_conversions.h"
+#include "base/time/time.h"
+#include "base/values.h"
+#include "components/sync/base/data_type.h"
+#include "components/sync/base/unique_position.h"
+#include "components/sync/protocol/app_setting_specifics.pb.h"
+#include "components/sync/protocol/app_specifics.pb.h"
+#include "components/sync/protocol/autofill_specifics.pb.h"
+#include "components/sync/protocol/bookmark_specifics.pb.h"
+#include "components/sync/protocol/collaboration_group_specifics.pb.h"
+#include "components/sync/protocol/contact_info_specifics.pb.h"
+#include "components/sync/protocol/cookie_specifics.pb.h"
+#include "components/sync/protocol/data_type_progress_marker.pb.h"
+#include "components/sync/protocol/device_info_specifics.pb.h"
+#include "components/sync/protocol/encryption.pb.h"
+#include "components/sync/protocol/entity_specifics.pb.h"
+#include "components/sync/protocol/extension_setting_specifics.pb.h"
+#include "components/sync/protocol/extension_specifics.pb.h"
+#include "components/sync/protocol/managed_user_setting_specifics.pb.h"
+#include "components/sync/protocol/nigori_specifics.pb.h"
+#include "components/sync/protocol/os_preference_specifics.pb.h"
+#include "components/sync/protocol/os_priority_preference_specifics.pb.h"
+#include "components/sync/protocol/password_specifics.pb.h"
+#include "components/sync/protocol/preference_specifics.pb.h"
+#include "components/sync/protocol/priority_preference_specifics.pb.h"
+#include "components/sync/protocol/product_comparison_specifics.pb.h"
+#include "components/sync/protocol/search_engine_specifics.pb.h"
+#include "components/sync/protocol/session_specifics.pb.h"
+#include "components/sync/protocol/sharing_message_specifics.pb.h"
+#include "components/sync/protocol/sync.pb.h"
+#include "components/sync/protocol/sync_entity.pb.h"
+#include "components/sync/protocol/theme_specifics.pb.h"
+#include "components/sync/protocol/typed_url_specifics.pb.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace syncer {
+namespace {
+
+using testing::Not;
+
+// Keep this file in sync with the .proto files in this directory.
+
+#define DEFINE_SPECIFICS_TO_VALUE_TEST(Key)                         \
+  TEST(ProtoValueConversionsTest, Proto_##Key##_SpecificsToValue) { \
+    sync_pb::EntitySpecifics specifics;                             \
+    specifics.mutable_##Key();                                      \
+    base::Value value = EntitySpecificsToValue(specifics);          \
+    ASSERT_TRUE(value.is_dict());                                   \
+    EXPECT_EQ(1u, value.GetDict().size());                          \
+  }
+
+// We'd also like to check if we changed any field in our messages. However,
+// that's hard to do: sizeof could work, but it's platform-dependent.
+// default_instance().ByteSizeLong() won't change for most changes, since most
+// of our fields are optional. So we just settle for comments in the proto
+// files.
+
+DEFINE_SPECIFICS_TO_VALUE_TEST(encrypted)
+
+static_assert(56 == syncer::GetNumDataTypes(),
+              "When adding a new field, add a DEFINE_SPECIFICS_TO_VALUE_TEST "
+              "for your field below, and optionally a test for the specific "
+              "conversions.");
+
+DEFINE_SPECIFICS_TO_VALUE_TEST(app)
+DEFINE_SPECIFICS_TO_VALUE_TEST(app_list)
+DEFINE_SPECIFICS_TO_VALUE_TEST(app_setting)
+DEFINE_SPECIFICS_TO_VALUE_TEST(arc_package)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_offer)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_profile)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_wallet)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_wallet_credential)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_wallet_usage)
+DEFINE_SPECIFICS_TO_VALUE_TEST(bookmark)
+DEFINE_SPECIFICS_TO_VALUE_TEST(collaboration_group)
+DEFINE_SPECIFICS_TO_VALUE_TEST(contact_info)
+DEFINE_SPECIFICS_TO_VALUE_TEST(cookie)
+DEFINE_SPECIFICS_TO_VALUE_TEST(device_info)
+DEFINE_SPECIFICS_TO_VALUE_TEST(dictionary)
+DEFINE_SPECIFICS_TO_VALUE_TEST(extension)
+DEFINE_SPECIFICS_TO_VALUE_TEST(extension_setting)
+DEFINE_SPECIFICS_TO_VALUE_TEST(history)
+DEFINE_SPECIFICS_TO_VALUE_TEST(history_delete_directive)
+DEFINE_SPECIFICS_TO_VALUE_TEST(incoming_password_sharing_invitation)
+DEFINE_SPECIFICS_TO_VALUE_TEST(managed_user_setting)
+DEFINE_SPECIFICS_TO_VALUE_TEST(nigori)
+DEFINE_SPECIFICS_TO_VALUE_TEST(os_preference)
+DEFINE_SPECIFICS_TO_VALUE_TEST(os_priority_preference)
+DEFINE_SPECIFICS_TO_VALUE_TEST(outgoing_password_sharing_invitation)
+DEFINE_SPECIFICS_TO_VALUE_TEST(password)
+DEFINE_SPECIFICS_TO_VALUE_TEST(plus_address)
+DEFINE_SPECIFICS_TO_VALUE_TEST(plus_address_setting)
+DEFINE_SPECIFICS_TO_VALUE_TEST(preference)
+DEFINE_SPECIFICS_TO_VALUE_TEST(printer)
+DEFINE_SPECIFICS_TO_VALUE_TEST(printers_authorization_server)
+DEFINE_SPECIFICS_TO_VALUE_TEST(priority_preference)
+DEFINE_SPECIFICS_TO_VALUE_TEST(product_comparison)
+DEFINE_SPECIFICS_TO_VALUE_TEST(reading_list)
+DEFINE_SPECIFICS_TO_VALUE_TEST(saved_tab_group)
+DEFINE_SPECIFICS_TO_VALUE_TEST(search_engine)
+DEFINE_SPECIFICS_TO_VALUE_TEST(security_event)
+DEFINE_SPECIFICS_TO_VALUE_TEST(send_tab_to_self)
+DEFINE_SPECIFICS_TO_VALUE_TEST(session)
+DEFINE_SPECIFICS_TO_VALUE_TEST(shared_tab_group_data)
+DEFINE_SPECIFICS_TO_VALUE_TEST(sharing_message)
+DEFINE_SPECIFICS_TO_VALUE_TEST(theme)
+DEFINE_SPECIFICS_TO_VALUE_TEST(typed_url)
+DEFINE_SPECIFICS_TO_VALUE_TEST(user_consent)
+DEFINE_SPECIFICS_TO_VALUE_TEST(user_event)
+DEFINE_SPECIFICS_TO_VALUE_TEST(wallet_metadata)
+DEFINE_SPECIFICS_TO_VALUE_TEST(web_apk)
+DEFINE_SPECIFICS_TO_VALUE_TEST(web_app)
+DEFINE_SPECIFICS_TO_VALUE_TEST(webauthn_credential)
+DEFINE_SPECIFICS_TO_VALUE_TEST(wifi_configuration)
+DEFINE_SPECIFICS_TO_VALUE_TEST(workspace_desk)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_valuable)
+DEFINE_SPECIFICS_TO_VALUE_TEST(autofill_valuable_setting)
+DEFINE_SPECIFICS_TO_VALUE_TEST(shared_tab_group_account_data)
+DEFINE_SPECIFICS_TO_VALUE_TEST(shared_comment)
+
+TEST(ProtoValueConversionsTest, AutofillWalletSpecificsToValue) {
+  sync_pb::AutofillWalletSpecifics specifics;
+  specifics.mutable_masked_card()->set_name_on_card("Igloo");
+  specifics.mutable_address()->set_recipient_name("John");
+  specifics.mutable_customer_data()->set_id("123456");
+  specifics.mutable_cloud_token_data()->set_masked_card_id("1111");
+
+  specifics.set_type(sync_pb::AutofillWalletSpecifics::UNKNOWN);
+  base::Value::Dict value =
+      AutofillWalletSpecificsToValue(specifics).TakeDict();
+  EXPECT_FALSE(value.contains("masked_card"));
+  EXPECT_FALSE(value.contains("address"));
+  EXPECT_FALSE(value.contains("customer_data"));
+  EXPECT_FALSE(value.contains("cloud_token_data"));
+
+  specifics.set_type(sync_pb::AutofillWalletSpecifics::MASKED_CREDIT_CARD);
+  value = AutofillWalletSpecificsToValue(specifics).TakeDict();
+  EXPECT_TRUE(value.contains("masked_card"));
+  EXPECT_FALSE(value.contains("address"));
+  EXPECT_FALSE(value.contains("customer_data"));
+  EXPECT_FALSE(value.contains("cloud_token_data"));
+
+  specifics.set_type(sync_pb::AutofillWalletSpecifics::POSTAL_ADDRESS);
+  value = AutofillWalletSpecificsToValue(specifics).TakeDict();
+  EXPECT_FALSE(value.contains("masked_card"));
+  EXPECT_TRUE(value.contains("address"));
+  EXPECT_FALSE(value.contains("customer_data"));
+  EXPECT_FALSE(value.contains("cloud_token_data"));
+
+  specifics.set_type(sync_pb::AutofillWalletSpecifics::CUSTOMER_DATA);
+  value = AutofillWalletSpecificsToValue(specifics).TakeDict();
+  EXPECT_FALSE(value.contains("masked_card"));
+  EXPECT_FALSE(value.contains("address"));
+  EXPECT_TRUE(value.contains("customer_data"));
+  EXPECT_FALSE(value.contains("cloud_token_data"));
+
+  specifics.set_type(
+      sync_pb::AutofillWalletSpecifics::CREDIT_CARD_CLOUD_TOKEN_DATA);
+  value = AutofillWalletSpecificsToValue(specifics).TakeDict();
+  EXPECT_FALSE(value.contains("masked_card"));
+  EXPECT_FALSE(value.contains("address"));
+  EXPECT_FALSE(value.contains("customer_data"));
+  EXPECT_TRUE(value.contains("cloud_token_data"));
+}
+
+TEST(ProtoValueConversionsTest, BookmarkSpecificsData) {
+  const base::Time creation_time(base::Time::Now());
+  const std::string icon_url = "http://www.google.com/favicon.ico";
+  sync_pb::BookmarkSpecifics specifics;
+  specifics.set_creation_time_us(creation_time.ToInternalValue());
+  specifics.set_icon_url(icon_url);
+  sync_pb::MetaInfo* meta_1 = specifics.add_meta_info();
+  meta_1->set_key("key1");
+  meta_1->set_value("value1");
+  sync_pb::MetaInfo* meta_2 = specifics.add_meta_info();
+  meta_2->set_key("key2");
+  meta_2->set_value("value2");
+
+  base::Value::Dict value = BookmarkSpecificsToValue(specifics).TakeDict();
+  EXPECT_FALSE(value.empty());
+  const std::string* encoded_time = value.FindString("creation_time_us");
+  EXPECT_TRUE(encoded_time);
+  EXPECT_EQ(base::NumberToString(creation_time.ToInternalValue()),
+            *encoded_time);
+  const std::string* encoded_icon_url = value.FindString("icon_url");
+  EXPECT_TRUE(encoded_icon_url);
+  EXPECT_EQ(icon_url, *encoded_icon_url);
+
+  const base::Value::List* meta_info_list = value.FindList("meta_info");
+
+  EXPECT_EQ(2u, meta_info_list->size());
+  std::string meta_key;
+  std::string meta_value;
+  const auto& meta_info_value = (*meta_info_list)[0].GetDict();
+  ASSERT_TRUE((*meta_info_list)[0].is_dict());
+  EXPECT_STREQ("key1", meta_info_value.FindString("key")->c_str());
+  EXPECT_STREQ("value1", meta_info_value.FindString("value")->c_str());
+  const auto& meta_info_value_1 = (*meta_info_list)[1].GetDict();
+  ASSERT_TRUE((*meta_info_list)[1].is_dict());
+  EXPECT_STREQ("key2", meta_info_value_1.FindString("key")->c_str());
+  EXPECT_STREQ("value2", meta_info_value_1.FindString("value")->c_str());
+}
+
+TEST(ProtoValueConversionsTest, UniquePositionToValue) {
+  sync_pb::SyncEntity entity;
+  entity.mutable_unique_position()->set_custom_compressed_v1("test");
+
+  base::Value::Dict value =
+      SyncEntityToValue(entity, {.include_specifics = false}).TakeDict();
+  const std::string* unique_position = value.FindString("unique_position");
+  EXPECT_TRUE(unique_position);
+
+  std::string expected_unique_position =
+      UniquePosition::FromProto(entity.unique_position()).ToDebugString();
+  EXPECT_EQ(expected_unique_position, *unique_position);
+}
+
+TEST(ProtoValueConversionsTest, SyncEntityToValueIncludeSpecifics) {
+  sync_pb::SyncEntity entity;
+  entity.mutable_specifics();
+
+  base::Value::Dict value =
+      SyncEntityToValue(entity, {.include_specifics = true}).TakeDict();
+  EXPECT_TRUE(value.FindDict("specifics"));
+
+  value = SyncEntityToValue(entity, {.include_specifics = false}).TakeDict();
+  EXPECT_FALSE(value.FindDict("specifics"));
+}
+
+namespace {
+// Returns whether the given value has specifics under the entries in the given
+// path.
+bool ValueHasSpecifics(const base::Value::Dict& value,
+                       const std::string& path) {
+  const base::Value::List* entities_list = value.FindListByDottedPath(path);
+  if (!entities_list) {
+    return false;
+  }
+
+  const base::Value& entry_dictionary_value = (*entities_list)[0];
+  if (!entry_dictionary_value.is_dict()) {
+    return false;
+  }
+
+  const base::Value::Dict& entry_dictionary = entry_dictionary_value.GetDict();
+  return entry_dictionary.FindDict("specifics") != nullptr;
+}
+
+MATCHER(ValueHasNonEmptyGetUpdateTriggers, "") {
+  const base::Value::Dict& value_dict = arg;
+
+  const base::Value::List* entities_list =
+      value_dict.FindListByDottedPath("get_updates.from_progress_marker");
+  if (!entities_list) {
+    *result_listener << "no from_progress_marker list";
+    return false;
+  }
+
+  const base::Value& entry_dictionary_value = entities_list->front();
+  if (!entry_dictionary_value.is_dict()) {
+    *result_listener << "from_progress_marker does not contain a dictionary";
+    return false;
+  }
+
+  const base::Value::Dict& entry_dictionary = entry_dictionary_value.GetDict();
+  const base::Value::Dict* get_update_triggers_dictionary =
+      entry_dictionary.FindDict("get_update_triggers");
+  if (!get_update_triggers_dictionary) {
+    *result_listener << "no get_update_triggers dictionary";
+    return false;
+  }
+
+  return !get_update_triggers_dictionary->empty();
+}
+}  // namespace
+
+// Create a ClientToServerMessage with an EntitySpecifics.  Converting it to
+// a value should respect the `include_specifics` flag.
+TEST(ProtoValueConversionsTest, ClientToServerMessageToValue) {
+  sync_pb::ClientToServerMessage message;
+  sync_pb::CommitMessage* commit_message = message.mutable_commit();
+  sync_pb::SyncEntity* entity = commit_message->add_entries();
+  entity->mutable_specifics();
+
+  base::Value::Dict value_with_specifics =
+      ClientToServerMessageToValue(message, {.include_specifics = true})
+          .TakeDict();
+  EXPECT_FALSE(value_with_specifics.empty());
+  EXPECT_TRUE(ValueHasSpecifics(value_with_specifics, "commit.entries"));
+
+  base::Value::Dict value_without_specifics =
+      ClientToServerMessageToValue(message, {.include_specifics = false})
+          .TakeDict();
+  EXPECT_FALSE(value_without_specifics.empty());
+  EXPECT_FALSE(ValueHasSpecifics(value_without_specifics, "commit.entries"));
+}
+
+TEST(ProtoValueConversionsTest, ClientToServerMessageToValueGUTriggers) {
+  sync_pb::ClientToServerMessage message;
+  sync_pb::GetUpdateTriggers* get_update_triggers =
+      message.mutable_get_updates()
+          ->add_from_progress_marker()
+          ->mutable_get_update_triggers();
+  get_update_triggers->set_client_dropped_hints(false);
+  get_update_triggers->set_server_dropped_hints(false);
+  get_update_triggers->set_datatype_refresh_nudges(0);
+  get_update_triggers->set_local_modification_nudges(0);
+  get_update_triggers->set_initial_sync_in_progress(false);
+  get_update_triggers->set_sync_for_resolve_conflict_in_progress(false);
+
+  base::Value::Dict value_with_full_gu_triggers =
+      ClientToServerMessageToValue(message,
+                                   {.include_full_get_update_triggers = true})
+          .TakeDict();
+  EXPECT_FALSE(value_with_full_gu_triggers.empty());
+  EXPECT_THAT(value_with_full_gu_triggers, ValueHasNonEmptyGetUpdateTriggers());
+
+  base::Value::Dict value_without_full_gu_triggers =
+      ClientToServerMessageToValue(message,
+                                   {.include_full_get_update_triggers = false})
+          .TakeDict();
+  EXPECT_FALSE(value_without_full_gu_triggers.empty());
+  EXPECT_THAT(value_without_full_gu_triggers,
+              Not(ValueHasNonEmptyGetUpdateTriggers()));
+}
+
+// Create a ClientToServerResponse with an EntitySpecifics.  Converting it to
+// a value should respect the `include_specifics` flag.
+TEST(ProtoValueConversionsTest, ClientToServerResponseToValue) {
+  sync_pb::ClientToServerResponse message;
+  sync_pb::GetUpdatesResponse* response = message.mutable_get_updates();
+  sync_pb::SyncEntity* entity = response->add_entries();
+  entity->mutable_specifics();
+
+  base::Value::Dict value_with_specifics =
+      ClientToServerResponseToValue(message, {.include_specifics = true})
+          .TakeDict();
+  EXPECT_FALSE(value_with_specifics.empty());
+  EXPECT_TRUE(ValueHasSpecifics(value_with_specifics, "get_updates.entries"));
+
+  base::Value::Dict value_without_specifics =
+      ClientToServerResponseToValue(message, {.include_specifics = false})
+          .TakeDict();
+  EXPECT_FALSE(value_without_specifics.empty());
+  EXPECT_FALSE(
+      ValueHasSpecifics(value_without_specifics, "get_updates.entries"));
+}
+
+TEST(ProtoValueConversionsTest, CompareSpecificsData) {
+  sync_pb::ProductComparisonSpecifics specifics;
+  specifics.set_uuid("my_uuid");
+  specifics.set_creation_time_unix_epoch_millis(1708532099);
+  specifics.set_update_time_unix_epoch_millis(1708642103);
+  specifics.set_name("my_name");
+  specifics.add_data();
+  specifics.mutable_data(0)->set_url("https://www.foo.com");
+  specifics.add_data();
+  specifics.mutable_data(1)->set_url("https://www.bar.com");
+
+  base::Value::Dict value =
+      ProductComparisonSpecificsToValue(specifics).TakeDict();
+  EXPECT_FALSE(value.empty());
+  EXPECT_TRUE(value.FindString("uuid"));
+  EXPECT_STREQ("my_uuid", value.FindString("uuid")->c_str());
+  EXPECT_TRUE(value.FindString("creation_time_unix_epoch_millis"));
+  EXPECT_STREQ("1708532099",
+               value.FindString("creation_time_unix_epoch_millis")->c_str());
+  EXPECT_TRUE(value.FindString("update_time_unix_epoch_millis"));
+  EXPECT_STREQ("1708642103",
+               value.FindString("update_time_unix_epoch_millis")->c_str());
+  EXPECT_TRUE(value.FindString("name"));
+  EXPECT_STREQ("my_name", value.FindString("name")->c_str());
+  const base::Value::List* data_list = value.FindList("data");
+  EXPECT_TRUE(data_list);
+  EXPECT_EQ(2u, data_list->size());
+  EXPECT_TRUE((*data_list)[0].GetDict().FindString("url"));
+  EXPECT_STREQ("https://www.foo.com",
+               (*data_list)[0].GetDict().FindString("url")->c_str());
+  EXPECT_TRUE((*data_list)[1].GetDict().FindString("url"));
+  EXPECT_STREQ("https://www.bar.com",
+               (*data_list)[1].GetDict().FindString("url")->c_str());
+}
+
+}  // namespace
+}  // namespace syncer
diff --git a/pyhindsight/lib/components/sync/protocol/proto_visitors.h b/pyhindsight/lib/components/sync/protocol/proto_visitors.h
new file mode 100644
index 0000000..cf0615c
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/proto_visitors.h
@@ -0,0 +1,2154 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SYNC_PROTOCOL_PROTO_VISITORS_H_
+#define COMPONENTS_SYNC_PROTOCOL_PROTO_VISITORS_H_
+
+#include "components/sync/base/data_type.h"
+#include "components/sync/protocol/app_list_specifics.pb.h"
+#include "components/sync/protocol/app_setting_specifics.pb.h"
+#include "components/sync/protocol/app_specifics.pb.h"
+#include "components/sync/protocol/arc_package_specifics.pb.h"
+#include "components/sync/protocol/autofill_offer_specifics.pb.h"
+#include "components/sync/protocol/autofill_specifics.pb.h"
+#include "components/sync/protocol/autofill_valuable_specifics.pb.h"
+#include "components/sync/protocol/autofill_wallet_credential_specifics.pb.h"
+#include "components/sync/protocol/autofill_wallet_usage_specifics.pb.h"
+#include "components/sync/protocol/bookmark_specifics.pb.h"
+#include "components/sync/protocol/collaboration_group_specifics.pb.h"
+#include "components/sync/protocol/contact_info_specifics.pb.h"
+#include "components/sync/protocol/cookie_specifics.pb.h"
+#include "components/sync/protocol/data_type_progress_marker.pb.h"
+#include "components/sync/protocol/data_type_state.pb.h"
+#include "components/sync/protocol/deletion_origin.pb.h"
+#include "components/sync/protocol/dictionary_specifics.pb.h"
+#include "components/sync/protocol/encryption.pb.h"
+#include "components/sync/protocol/entity_metadata.pb.h"
+#include "components/sync/protocol/entity_specifics.pb.h"
+#include "components/sync/protocol/extension_setting_specifics.pb.h"
+#include "components/sync/protocol/extension_specifics.pb.h"
+#include "components/sync/protocol/history_delete_directive_specifics.pb.h"
+#include "components/sync/protocol/history_specifics.pb.h"
+#include "components/sync/protocol/nigori_local_data.pb.h"
+#include "components/sync/protocol/nigori_specifics.pb.h"
+#include "components/sync/protocol/note_entity.pb.h"
+#include "components/sync/protocol/os_preference_specifics.pb.h"
+#include "components/sync/protocol/os_priority_preference_specifics.pb.h"
+#include "components/sync/protocol/password_sharing_invitation_specifics.pb.h"
+#include "components/sync/protocol/password_specifics.pb.h"
+#include "components/sync/protocol/persisted_entity_data.pb.h"
+#include "components/sync/protocol/plus_address_setting_specifics.pb.h"
+#include "components/sync/protocol/plus_address_specifics.pb.h"
+#include "components/sync/protocol/power_bookmark_specifics.pb.h"
+#include "components/sync/protocol/preference_specifics.pb.h"
+#include "components/sync/protocol/printer_specifics.pb.h"
+#include "components/sync/protocol/printers_authorization_server_specifics.pb.h"
+#include "components/sync/protocol/priority_preference_specifics.pb.h"
+#include "components/sync/protocol/product_comparison_specifics.pb.h"
+#include "components/sync/protocol/proto_enum_conversions.h"
+#include "components/sync/protocol/proto_value_conversions.h"
+#include "components/sync/protocol/reading_list_specifics.pb.h"
+#include "components/sync/protocol/saved_tab_group_specifics.pb.h"
+#include "components/sync/protocol/search_engine_specifics.pb.h"
+#include "components/sync/protocol/send_tab_to_self_specifics.pb.h"
+#include "components/sync/protocol/session_specifics.pb.h"
+#include "components/sync/protocol/shared_comment_specifics.pb.h"
+#include "components/sync/protocol/shared_tab_group_data_specifics.pb.h"
+#include "components/sync/protocol/sharing_message_specifics.pb.h"
+#include "components/sync/protocol/sync.pb.h"
+#include "components/sync/protocol/sync_entity.pb.h"
+#include "components/sync/protocol/sync_invalidations_payload.pb.h"
+#include "components/sync/protocol/tab_group_attribution_metadata.pb.h"
+#include "components/sync/protocol/theme_specifics.pb.h"
+#include "components/sync/protocol/theme_specifics_ios.pb.h"
+#include "components/sync/protocol/theme_types.pb.h"
+#include "components/sync/protocol/typed_url_specifics.pb.h"
+#include "components/sync/protocol/unencrypted_sharing_message.pb.h"
+#include "components/sync/protocol/unique_position.pb.h"
+#include "components/sync/protocol/user_consent_specifics.pb.h"
+#include "components/sync/protocol/user_event_specifics.pb.h"
+#include "components/sync/protocol/web_apk_specifics.pb.h"
+#include "components/sync/protocol/web_app_specifics.pb.h"
+#include "components/sync/protocol/webauthn_credential_specifics.pb.h"
+#include "components/sync/protocol/workspace_desk_specifics.pb.h"
+
+// This file implements VisitProtoFields() functions for sync protos.
+//
+// VisitProtoFields(visitor, proto) calls `visitor` for each field in
+// `proto`. When called, `visitor` gets passed `proto`, field name and
+// field value.
+//
+// VisitProtoFields() used to implement two distinctive features:
+// 1. Serialization into base::Value::Dict
+// 2. Proto memory usage estimation
+//
+// To achieve that it's very important for VisitProtoFields() to be free
+// of any logic. It must just call visitor for each field in a proto.
+//
+// Logic (like clobbering sensitive fields) must be implemented in visitors.
+// For example see how ToValueVisitor (from proto_value_conversions.cc)
+// implements various customizations.
+
+#define VISIT_(Kind, field) \
+  if (proto.has_##field())  \
+  visitor.Visit##Kind(proto, #field, proto.field())
+
+// Generic version, calls visitor.Visit(). Handles almost everything except
+// for special cases below.
+#define VISIT(field) VISIT_(, field)
+
+// 'bytes' protobuf type maps to std::string, and is indistinguishable
+// from 'string' type. To solve that 'bytes' fields are special cased to
+// call visitor.VisitBytes().
+#define VISIT_BYTES(field) VISIT_(Bytes, field)
+
+// We could use template magic (std::is_enum) to handle enums, but that would
+// complicate visitors, and besides we already have special case for 'bytes',
+// so just add one more special case. Calls visitor.VisitEnum().
+#define VISIT_ENUM(field) VISIT_(Enum, field)
+
+// Repeated fields are always present, so there are no 'has_<field>' methods.
+// This macro unconditionally calls visitor.Visit().
+#define VISIT_REP(field) visitor.Visit(proto, #field, proto.field());
+
+// Repeated fields are always present, so there are no 'has_<field>' methods.
+// This macro unconditionally calls visitor.VisitBytes().
+#define VISIT_REP_BYTES(field) visitor.VisitBytes(proto, #field, proto.field());
+
+// Values that are secrets do not have their contents reported in debugging
+// output, only their lengths, but are still counted for things like memory
+// estimation.
+#define VISIT_SECRET(field) VISIT_(Secret, field)
+
+#define VISIT_PROTO_FIELDS(proto) \
+  template <class V>              \
+  void VisitProtoFields(V& visitor, proto)
+
+namespace syncer {
+
+VISIT_PROTO_FIELDS(const sync_pb::AppListSpecifics& proto) {
+  VISIT(item_id);
+  VISIT_ENUM(item_type);
+  VISIT(item_name);
+  VISIT(parent_id);
+  VISIT(item_ordinal);
+  VISIT(item_pin_ordinal);
+  VISIT(promise_package_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AppNotificationSettings& proto) {
+  VISIT(initial_setup_done);
+  VISIT(disabled);
+  VISIT(oauth_client_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AppSettingSpecifics& proto) {
+  VISIT(extension_setting);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AppSpecifics& proto) {
+  VISIT(extension);
+  VISIT(notification_settings);
+  VISIT(app_launch_ordinal);
+  VISIT(page_ordinal);
+  VISIT_ENUM(launch_type);
+  VISIT_REP(linked_app_icons);
+  VISIT(bookmark_app_url);
+  VISIT(bookmark_app_description);
+  VISIT(bookmark_app_icon_color);
+  VISIT(bookmark_app_scope);
+  VISIT(bookmark_app_theme_color);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ArcPackageSpecifics& proto) {
+  VISIT(package_name);
+  VISIT(package_version);
+  VISIT(last_backup_android_id);
+  VISIT(last_backup_time);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillOfferSpecifics& proto) {
+  VISIT(id);
+  VISIT(offer_details_url);
+  VISIT_REP(merchant_domain);
+  VISIT_REP(merchant_app_package);
+  VISIT(offer_expiry_date);
+  VISIT(card_linked_offer_data);
+  VISIT(promo_code_offer_data);
+  VISIT(display_strings);
+  VISIT(percentage_reward);
+  VISIT(fixed_amount_reward);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AutofillOfferSpecifics::CardLinkedOfferData& proto) {
+  VISIT_REP(instrument_id);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AutofillOfferSpecifics::PromoCodeOfferData& proto) {
+  VISIT(promo_code);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AutofillOfferSpecifics::DisplayStrings& proto) {
+  VISIT(value_prop_text);
+  VISIT(see_details_text_mobile);
+  VISIT(see_details_text_desktop);
+  VISIT(usage_instructions_text_mobile);
+  VISIT(usage_instructions_text_desktop);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AutofillOfferSpecifics::PercentageReward& proto) {
+  VISIT(percentage);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AutofillOfferSpecifics::FixedAmountReward& proto) {
+  VISIT(amount);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillProfileSpecifics& proto) {
+  VISIT(guid);
+  VISIT(deprecated_origin);
+  VISIT(use_count);
+  VISIT(use_date);
+  VISIT(profile_label);
+  VISIT_REP(name_first);
+  VISIT_REP(name_middle);
+  VISIT_REP(name_last_prefix);
+  VISIT_REP(name_last_core);
+  VISIT_REP(name_last_first);
+  VISIT_REP(name_last_conjunction);
+  VISIT_REP(name_last_second);
+  VISIT_REP(name_last);
+  VISIT_REP(name_full);
+
+  VISIT_REP(name_first_status);
+  VISIT_REP(name_middle_status);
+  VISIT_REP(name_last_prefix_status);
+  VISIT_REP(name_last_core_status);
+  VISIT_REP(name_last_first_status);
+  VISIT_REP(name_last_conjunction_status);
+  VISIT_REP(name_last_second_status);
+  VISIT_REP(name_last_status);
+  VISIT_REP(name_full_status);
+
+  VISIT(alternative_full_name);
+  VISIT(alternative_given_name);
+  VISIT(alternative_family_name);
+
+  VISIT_ENUM(alternative_full_name_status);
+  VISIT_ENUM(alternative_given_name_status);
+  VISIT_ENUM(alternative_family_name_status);
+
+  VISIT_REP(email_address);
+  VISIT(company_name);
+
+  VISIT(address_home_line1);
+  VISIT(address_home_line2);
+  VISIT(address_home_city);
+  VISIT(address_home_state);
+  VISIT(address_home_zip);
+  VISIT(address_home_zip_prefix);
+  VISIT(address_home_zip_suffix);
+  VISIT(address_home_country);
+  VISIT(address_home_landmark);
+  VISIT(address_home_overflow);
+  VISIT(address_home_between_streets);
+  VISIT(address_home_between_streets_1);
+  VISIT(address_home_between_streets_2);
+  VISIT(address_home_between_streets_or_landmark);
+  VISIT(address_home_overflow_and_landmark);
+  VISIT(address_home_admin_level_2);
+  VISIT(address_home_street_address);
+  VISIT(address_home_sorting_code);
+  VISIT(address_home_dependent_locality);
+  VISIT(address_home_thoroughfare_name);
+  VISIT(address_home_thoroughfare_number);
+  VISIT(address_home_subpremise_name);
+  VISIT(address_home_apt);
+  VISIT(address_home_apt_num);
+  VISIT(address_home_apt_type);
+  VISIT(address_home_street_location_and_locality);
+  VISIT(address_home_thoroughfare_number_and_apt);
+
+  VISIT_ENUM(address_home_city_status);
+  VISIT_ENUM(address_home_state_status);
+  VISIT_ENUM(address_home_zip_status);
+  VISIT_ENUM(address_home_zip_prefix_status);
+  VISIT_ENUM(address_home_zip_suffix_status);
+  VISIT_ENUM(address_home_country_status);
+  VISIT_ENUM(address_home_landmark_status);
+  VISIT_ENUM(address_home_overflow_status);
+  VISIT_ENUM(address_home_between_streets_status);
+  VISIT_ENUM(address_home_between_streets_1_status);
+  VISIT_ENUM(address_home_between_streets_2_status);
+  VISIT_ENUM(address_home_between_streets_or_landmark_status);
+  VISIT_ENUM(address_home_overflow_and_landmark_status);
+  VISIT_ENUM(address_home_admin_level_2_status);
+  VISIT_ENUM(address_home_street_address_status);
+  VISIT_ENUM(address_home_sorting_code_status);
+  VISIT_ENUM(address_home_dependent_locality_status);
+  VISIT_ENUM(address_home_thoroughfare_name_status);
+  VISIT_ENUM(address_home_thoroughfare_number_status);
+  VISIT_ENUM(address_home_subpremise_name_status);
+  VISIT_ENUM(address_home_apt_status);
+  VISIT_ENUM(address_home_apt_num_status);
+  VISIT_ENUM(address_home_apt_type_status);
+  VISIT_ENUM(address_home_street_location_and_locality_status);
+  VISIT_ENUM(address_home_thoroughfare_number_and_apt_status);
+
+  VISIT(address_home_language_code);
+  VISIT_REP(phone_home_whole_number);
+  VISIT(validity_state_bitfield);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillSpecifics& proto) {
+  VISIT(name);
+  VISIT(value);
+  VISIT_REP(usage_timestamp);
+  VISIT(profile);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillWalletCredentialSpecifics& proto) {
+  VISIT(instrument_id);
+  VISIT_SECRET(cvc);
+  VISIT(last_updated_time_unix_epoch_millis);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillWalletUsageSpecifics& proto) {
+  VISIT(guid);
+  VISIT(virtual_card_usage_data);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AutofillWalletUsageSpecifics::VirtualCardUsageData& proto) {
+  VISIT(instrument_id);
+  VISIT(virtual_card_last_four);
+  VISIT(merchant_url);
+  VISIT(merchant_app_package);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillWalletSpecifics& proto) {
+  VISIT_ENUM(type);
+  VISIT(masked_card);
+  VISIT(address);
+  VISIT(customer_data);
+  VISIT(cloud_token_data);
+  VISIT(payment_instrument);
+  VISIT(payment_instrument_creation_option);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::BnplCreationOption& proto) {
+  VISIT(issuer_id);
+  VISIT_REP(eligible_price_range);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::BnplIssuerDetails& proto) {
+  VISIT(issuer_id);
+  VISIT_REP(eligible_price_range);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::BookmarkSpecifics& proto) {
+  VISIT(url);
+  VISIT_BYTES(favicon);
+  VISIT(guid);
+  VISIT(legacy_canonicalized_title);
+  VISIT(creation_time_us);
+  VISIT(icon_url);
+  VISIT_REP(meta_info);
+  VISIT(full_title);
+  VISIT(parent_guid);
+  VISIT_ENUM(type);
+  VISIT(unique_position);
+  VISIT(last_used_time_us);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ChromiumExtensionsActivity& proto) {
+  VISIT(extension_id);
+  VISIT(bookmark_writes_since_last_commit);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CollaborationGroupSpecifics& proto) {
+  VISIT(collaboration_id);
+  VISIT(changed_at_timestamp_millis_since_unix_epoch);
+  VISIT(consistency_token);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ComparisonData& proto) {
+  VISIT(url);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ProductComparison& proto) {
+  VISIT(name);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ProductComparisonItem& proto) {
+  VISIT(product_comparison_uuid);
+  VISIT(url);
+  VISIT(unique_position);
+  VISIT(title);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ProductComparisonSpecifics& proto) {
+  VISIT(uuid);
+  VISIT(creation_time_unix_epoch_millis);
+  VISIT(update_time_unix_epoch_millis);
+  VISIT(name);
+  VISIT_REP(data);
+  VISIT(product_comparison);
+  VISIT(product_comparison_item);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ContactInfoSpecifics& proto) {
+  VISIT(guid);
+  VISIT_ENUM(address_type);
+  VISIT(use_count);
+  VISIT(use_date_unix_epoch_seconds);
+  VISIT(use_date2_unix_epoch_seconds);
+  VISIT(use_date3_unix_epoch_seconds);
+  VISIT(date_modified_unix_epoch_seconds);
+  VISIT(language_code);
+  VISIT(profile_label);
+  VISIT(initial_creator_id);
+  VISIT(last_modifier_id);
+  VISIT(name_first);
+  VISIT(name_middle);
+  VISIT(name_last);
+  VISIT(name_last_prefix);
+  VISIT(name_last_core);
+  VISIT(name_last_first);
+  VISIT(name_last_conjunction);
+  VISIT(name_last_second);
+  VISIT(name_full);
+  VISIT(alternative_full_name);
+  VISIT(alternative_given_name);
+  VISIT(alternative_family_name);
+  VISIT(email_address);
+  VISIT(company_name);
+  VISIT(address_city);
+  VISIT(address_state);
+  VISIT(address_zip);
+  VISIT(address_zip_prefix);
+  VISIT(address_zip_suffix);
+  VISIT(address_country);
+  VISIT(address_street_address);
+  VISIT(address_sorting_code);
+  VISIT(address_dependent_locality);
+  VISIT(address_thoroughfare_name);
+  VISIT(address_thoroughfare_number);
+  VISIT(address_subpremise_name);
+  VISIT(address_apt);
+  VISIT(address_apt_num);
+  VISIT(address_apt_type);
+  VISIT(address_floor);
+  VISIT(address_landmark);
+  VISIT(address_between_streets);
+  VISIT(address_admin_level_2);
+  VISIT(phone_home_whole_number);
+  VISIT(address_street_location);
+  VISIT(address_overflow);
+  VISIT(address_between_streets_1);
+  VISIT(address_between_streets_2);
+  VISIT(address_between_streets_or_landmark);
+  VISIT(address_overflow_and_landmark);
+  VISIT(address_street_location_and_locality);
+  VISIT(address_thoroughfare_number_and_apt);
+  VISIT(invisible_in_autofill);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ContactInfoSpecifics::Observation& proto) {
+  VISIT(type);
+  VISIT(form_hash);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ContactInfoSpecifics::TokenMetadata& proto) {
+  VISIT_ENUM(status);
+  VISIT_REP(observations);
+  VISIT(value_hash);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ContactInfoSpecifics::StringToken& proto) {
+  VISIT(value);
+  VISIT(metadata);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CookieSpecifics& proto) {
+  VISIT(unique_key);
+  VISIT(name);
+  VISIT(value);
+  VISIT(domain);
+  VISIT(path);
+  VISIT(creation_time_windows_epoch_micros);
+  VISIT(expiry_time_windows_epoch_micros);
+  VISIT(last_access_time_windows_epoch_micros);
+  VISIT(last_update_time_windows_epoch_micros);
+  VISIT(secure);
+  VISIT(httponly);
+  VISIT_ENUM(site_restrictions);
+  VISIT_ENUM(priority);
+  VISIT_ENUM(source_scheme);
+  VISIT(partition_key);
+  VISIT(source_port);
+  VISIT_ENUM(source_type);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::CookieSpecifics::SerializedCookiePartitionKey& proto) {
+  VISIT(top_level_site);
+  VISIT(has_cross_site_ancestor);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CustomNudgeDelay& proto) {
+  VISIT(datatype_id);
+  VISIT(delay_ms);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ClientCommand& proto) {
+  VISIT(set_sync_poll_interval);
+  VISIT(max_commit_batch_size);
+  VISIT(throttle_delay_seconds);
+  VISIT(client_invalidation_hint_buffer_size);
+  VISIT_REP(custom_nudge_delays);
+  VISIT(extension_types_max_tokens);
+  VISIT(extension_types_refill_interval_seconds);
+  VISIT(extension_types_depleted_quota_nudge_delay_seconds);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ClientConfigParams& proto) {
+  VISIT_REP(enabled_type_ids);
+  VISIT(tabs_datatype_enabled);
+  VISIT(cookie_jar_mismatch);
+  VISIT(single_client);
+  VISIT_REP(devices_fcm_registration_tokens);
+  VISIT(single_client_with_standalone_invalidations);
+  VISIT_REP(fcm_registration_tokens_for_interested_clients);
+  VISIT(single_client_with_old_invalidations);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ClientStatus& proto) {
+  VISIT(hierarchy_conflict_detected);
+  VISIT(is_sync_feature_enabled);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ClientToServerMessage& proto) {
+  VISIT(share);
+  VISIT(protocol_version);
+  VISIT(commit);
+  VISIT(get_updates);
+  VISIT(store_birthday);
+  VISIT(debug_info);
+  VISIT(client_status);
+  VISIT(invalidator_client_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ClientToServerResponse& proto) {
+  VISIT(commit);
+  VISIT(get_updates);
+  VISIT(error);
+  VISIT_ENUM(error_code);
+  VISIT(error_message);
+  VISIT(store_birthday);
+  VISIT(client_command);
+  VISIT_REP(migrated_data_type_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ClientToServerResponse::Error& proto) {
+  VISIT_ENUM(error_type);
+  VISIT(error_description);
+  VISIT_ENUM(action);
+  VISIT_REP(error_data_type_ids);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommitMessage& proto) {
+  VISIT_REP(entries);
+  VISIT(cache_guid);
+  VISIT_REP(extensions_activity);
+  VISIT(config_params);
+  VISIT_REP(client_contexts);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommitResponse& proto) {
+  VISIT_REP(entryresponse);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommitResponse::EntryResponse& proto) {
+  VISIT_ENUM(response_type);
+  VISIT(id_string);
+  VISIT(version);
+  VISIT(error_message);
+  VISIT(mtime);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DataTypeContext& proto) {
+  VISIT(data_type_id);
+  VISIT(context);
+  VISIT(version);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DataTypeProgressMarker& proto) {
+  VISIT(data_type_id);
+  VISIT_BYTES(token);
+  VISIT(get_update_triggers);
+  VISIT(gc_directive);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GarbageCollectionDirective& proto) {
+  VISIT(version_watermark);
+  VISIT(collaboration_gc);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::GarbageCollectionDirective::CollaborationGarbageCollection&
+        proto) {
+  VISIT_REP(active_collaboration_ids);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DebugEventInfo& proto) {
+  VISIT_ENUM(singleton_event);
+  VISIT(sync_cycle_completed_event_info);
+  VISIT(nudging_datatype);
+  VISIT_REP(datatypes_notified_from_server);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DebugInfo& proto) {
+  VISIT_REP(events);
+  VISIT(cryptographer_ready);
+  VISIT(cryptographer_has_pending_keys);
+  VISIT(events_dropped);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DeletionOrigin& proto) {
+  VISIT(chromium_version);
+  VISIT(google_play_services_apk_version_name);
+  VISIT(file_name_hash);
+  VISIT(file_line_number);
+  VISIT(file_name_possibly_truncated);
+  VISIT(unique_source_tag_no_pii_possibly_truncated);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DeviceInfoSpecifics& proto) {
+  VISIT(cache_guid);
+  VISIT(client_name);
+  VISIT_ENUM(device_type);
+  VISIT(sync_user_agent);
+  VISIT(chrome_version);
+  VISIT(signin_scoped_device_id);
+  VISIT(model);
+  VISIT(manufacturer);
+  VISIT(last_updated_timestamp);
+  VISIT(feature_fields);
+  VISIT(sharing_fields);
+  VISIT(invalidation_fields);
+  VISIT(paask_fields);
+  VISIT(full_hardware_class);
+  VISIT(chrome_version_info);
+  VISIT(google_play_services_version_info);
+  VISIT_ENUM(os_type);
+  VISIT_ENUM(device_form_factor);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::EligiblePriceRange& proto) {
+  VISIT(currency);
+  VISIT(min_price_in_micros);
+  VISIT(max_price_in_micros);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::FeatureSpecificFields& proto) {
+  VISIT(send_tab_to_self_receiving_enabled);
+  VISIT_ENUM(send_tab_to_self_receiving_type);
+  VISIT(auto_sign_out_last_signin_timestamp_windows_epoch_micros);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharingSpecificFields& proto) {
+  VISIT_REP(enabled_features);
+  VISIT(sender_id_fcm_token_v2);
+  VISIT_BYTES(sender_id_p256dh_v2);
+  VISIT_BYTES(sender_id_auth_secret_v2);
+  VISIT(chime_representative_target_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PhoneAsASecurityKeySpecificFields& proto) {
+  VISIT(tunnel_server_domain);
+  VISIT_BYTES(contact_id);
+  VISIT(id);
+  VISIT_BYTES(peer_public_key_x962);
+  VISIT_BYTES(google_credential_id);
+  // `secret` is deliberately omitted to avoid including sensitive information
+  // in debugging output, which might be included in bug reports etc.
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ChromeVersionInfo& proto) {
+  VISIT(version_number);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GooglePlayServicesVersionInfo& proto) {
+  VISIT(apk_version_name);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DictionarySpecifics& proto) {
+  VISIT(word);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::EncryptedData& proto) {
+  VISIT(key_name);
+  VISIT_BYTES(blob);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::EntityMetadata& proto) {
+  VISIT(client_tag_hash);
+  VISIT(server_id);
+  VISIT(is_deleted);
+  VISIT(sequence_number);
+  VISIT(acked_sequence_number);
+  VISIT(server_version);
+  VISIT(creation_time);
+  VISIT(modification_time);
+  VISIT(specifics_hash);
+  VISIT(base_specifics_hash);
+  VISIT(possibly_trimmed_base_specifics);
+  VISIT(deleted_by_version);
+  VISIT(collaboration);
+  VISIT(deletion_origin);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::EntityMetadata::CollaborationMetadata& proto) {
+  VISIT(collaboration_id);
+  VISIT(creation_attribution);
+  VISIT(last_update_attribution);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::EntityMetadata::CollaborationMetadata::Attribution& proto) {
+  VISIT(obfuscated_gaia_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::EntitySpecifics& proto) {
+  static_assert(56 == GetNumDataTypes(),
+                "When adding a new protocol type, you will likely need to add "
+                "it here as well.");
+  VISIT(encrypted);
+  VISIT(app);
+  VISIT(app_list);
+  VISIT(app_setting);
+  VISIT(arc_package);
+  VISIT(autofill);
+  VISIT(autofill_offer);
+  VISIT(autofill_profile);
+  VISIT(autofill_valuable);
+  VISIT(autofill_valuable_setting);
+  VISIT(autofill_wallet);
+  VISIT(autofill_wallet_credential);
+  VISIT(autofill_wallet_usage);
+  VISIT(bookmark);
+  VISIT(collaboration_group);
+  VISIT(contact_info);
+  VISIT(cookie);
+  VISIT(device_info);
+  VISIT(dictionary);
+  VISIT(extension);
+  VISIT(extension_setting);
+  VISIT(history);
+  VISIT(history_delete_directive);
+  VISIT(incoming_password_sharing_invitation);
+  VISIT(managed_user_setting);
+  VISIT(nigori);
+  VISIT(os_preference);
+  VISIT(os_priority_preference);
+  VISIT(outgoing_password_sharing_invitation);
+  VISIT(password);
+  VISIT(plus_address);
+  VISIT(plus_address_setting);
+  VISIT(preference);
+  VISIT(printer);
+  VISIT(printers_authorization_server);
+  VISIT(priority_preference);
+  VISIT(product_comparison);
+  VISIT(reading_list);
+  VISIT(saved_tab_group);
+  VISIT(search_engine);
+  VISIT(security_event);
+  VISIT(send_tab_to_self);
+  VISIT(session);
+  VISIT(shared_comment);
+  VISIT(shared_tab_group_account_data);
+  VISIT(shared_tab_group_data);
+  VISIT(sharing_message);
+  VISIT(theme);
+  VISIT(typed_url);
+  VISIT(user_consent);
+  VISIT(user_event);
+  VISIT(wallet_metadata);
+  VISIT(web_apk);
+  VISIT(web_app);
+  VISIT(webauthn_credential);
+  VISIT(wifi_configuration);
+  VISIT(workspace_desk);
+  VISIT(webauthn_credential);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ExtensionSettingSpecifics& proto) {
+  VISIT(extension_id);
+  VISIT(key);
+  VISIT(value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ExtensionSpecifics& proto) {
+  VISIT(id);
+  VISIT(version);
+  VISIT(update_url);
+  VISIT(enabled);
+  VISIT(incognito_enabled);
+  VISIT(remote_install);
+  VISIT(all_urls_enabled);
+  VISIT(disable_reasons);
+  VISIT_REP(disable_reasons_list);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GetUpdateTriggers& proto) {
+  VISIT_REP(notification_hint);
+  VISIT(client_dropped_hints);
+  VISIT(invalidations_out_of_sync);
+  VISIT(local_modification_nudges);
+  VISIT(datatype_refresh_nudges);
+  VISIT(server_dropped_hints);
+  VISIT(initial_sync_in_progress);
+  VISIT(sync_for_resolve_conflict_in_progress);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GetUpdatesCallerInfo& proto) {
+  VISIT(notifications_enabled);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GetUpdatesMessage& proto) {
+  VISIT(caller_info);
+  VISIT(fetch_folders);
+  VISIT_REP(from_progress_marker);
+  VISIT(streaming);
+  VISIT(need_encryption_key);
+  VISIT_ENUM(get_updates_origin);
+  VISIT(is_retry);
+  VISIT_REP(client_contexts);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GetUpdatesResponse& proto) {
+  VISIT_REP(entries)
+  VISIT(changes_remaining);
+  VISIT_REP(new_progress_marker);
+  VISIT_REP(context_mutations);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GlobalIdDirective& proto) {
+  VISIT_REP(global_id);
+  VISIT(start_time_usec);
+  VISIT(end_time_usec);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::HistoryDeleteDirectiveSpecifics& proto) {
+  VISIT(global_id_directive);
+  VISIT(time_range_directive);
+  VISIT(url_directive);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::IncomingPasswordSharingInvitationSpecifics& proto) {
+  VISIT(guid);
+  VISIT(sender_info);
+  VISIT_BYTES(encrypted_password_sharing_invitation_data);
+  VISIT(client_only_unencrypted_data);
+  VISIT(recipient_key_version);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::InvalidationSpecificFields& proto) {
+  VISIT(instance_id_token);
+  VISIT_REP(interested_data_type_ids);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::LinkedAppIconInfo& proto) {
+  VISIT(url);
+  VISIT(size);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ManagedUserSettingSpecifics& proto) {
+  VISIT(name);
+  VISIT(value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::MetaInfo& proto) {
+  VISIT(key);
+  VISIT(value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DataTypeState& proto) {
+  VISIT(progress_marker);
+  VISIT(type_context);
+  VISIT(encryption_key_name);
+  VISIT_ENUM(initial_sync_state);
+  VISIT(cache_guid);
+  VISIT(authenticated_obfuscated_gaia_id);
+  VISIT_REP(invalidations);
+  VISIT(notes_enabled_before_initial_sync_for_passwords);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DataTypeState::Invalidation& proto) {
+  VISIT(hint);
+  VISIT(version);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::NavigationRedirect& proto) {
+  VISIT(url);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ReplacedNavigation& proto) {
+  VISIT(first_committed_url);
+  VISIT(first_timestamp_msec);
+  VISIT_ENUM(first_page_transition);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CryptographerData& proto) {
+  VISIT(key_bag);
+  VISIT(default_key_name);
+  VISIT(cross_user_sharing_keys);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CrossUserSharingKeys& proto) {
+  VISIT_REP(private_key);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CustomPassphraseKeyDerivationParams& proto) {
+  VISIT(custom_passphrase_key_derivation_method);
+  VISIT(custom_passphrase_key_derivation_salt);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::NigoriModel& proto) {
+  VISIT(cryptographer_data);
+  VISIT(current_keystore_key_name);
+  VISIT(pending_keys);
+  VISIT(passphrase_type);
+  VISIT(keystore_migration_time);
+  VISIT(custom_passphrase_time);
+  VISIT(custom_passphrase_key_derivation_params);
+  VISIT(encrypt_everything);
+  VISIT_REP(encrypted_types_specifics_field_number);
+  VISIT_REP(keystore_key);
+  VISIT(pending_keystore_decryptor_token);
+  VISIT(last_default_trusted_vault_key_name);
+  VISIT(trusted_vault_debug_info);
+  VISIT(cross_user_sharing_public_key);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::NigoriLocalData& proto) {
+  VISIT(data_type_state);
+  VISIT(entity_metadata);
+  VISIT(nigori_model);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CrossUserSharingPublicKey& proto) {
+  VISIT(version);
+  VISIT_BYTES(x25519_public_key);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CrossUserSharingPrivateKey& proto) {
+  VISIT(version);
+  VISIT(x25519_private_key);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::NigoriSpecifics& proto) {
+  VISIT(encryption_keybag);
+  VISIT(keybag_is_frozen);
+  VISIT(encrypt_everything);
+  VISIT(server_only_was_missing_keystore_migration_time);
+  VISIT(sync_tab_favicons);
+  VISIT(passphrase_type);
+  VISIT(keystore_decryptor_token);
+  VISIT(keystore_migration_time);
+  VISIT(custom_passphrase_time);
+  VISIT(custom_passphrase_key_derivation_method);
+  VISIT(custom_passphrase_key_derivation_salt);
+  VISIT(trusted_vault_debug_info);
+  VISIT(cross_user_sharing_public_key);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WebauthnCredentialSpecifics& proto) {
+  VISIT_BYTES(sync_id);
+  VISIT_BYTES(credential_id);
+  VISIT(rp_id);
+  VISIT_BYTES(user_id);
+  VISIT_REP_BYTES(newly_shadowed_credential_ids);
+  VISIT(creation_time);
+  VISIT(user_name);
+  VISIT(user_display_name);
+  VISIT(third_party_payments_support);
+  VISIT(last_used_time_windows_epoch_micros);
+  VISIT(key_version);
+  VISIT(device_authorization_key_version);
+  VISIT_SECRET(private_key);
+  VISIT_SECRET(encrypted);
+  VISIT_SECRET(security_domain_encrypted);
+  VISIT(edited_by_user);
+  VISIT(hidden);
+  VISIT(hidden_time);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::HistorySpecifics::PageTransition& proto) {
+  VISIT_ENUM(core_transition);
+  VISIT(blocked);
+  VISIT(forward_back);
+  VISIT(from_address_bar);
+  VISIT(home_page);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::HistorySpecifics::RedirectEntry& proto) {
+  VISIT(originator_visit_id);
+  VISIT(url);
+  VISIT(title);
+  VISIT(hidden);
+  VISIT_ENUM(redirect_type);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::HistorySpecifics::Category& proto) {
+  VISIT(id);
+  VISIT(weight);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::HistorySpecifics& proto) {
+  VISIT(visit_time_windows_epoch_micros);
+  VISIT(originator_cache_guid);
+  VISIT_REP(redirect_entries);
+  VISIT(redirect_chain_start_incomplete);
+  VISIT(redirect_chain_end_incomplete);
+  VISIT(redirect_chain_middle_trimmed);
+  VISIT(page_transition);
+  VISIT(originator_referring_visit_id);
+  VISIT(originator_opener_visit_id);
+  VISIT(originator_cluster_id);
+  VISIT(visit_duration_micros);
+  VISIT_ENUM(browser_type);
+  VISIT(window_id);
+  VISIT(tab_id);
+  VISIT(task_id);
+  VISIT(root_task_id);
+  VISIT(parent_task_id);
+  VISIT(http_response_code);
+  VISIT(page_language);
+  VISIT_ENUM(password_state);
+  VISIT(favicon_url);
+  VISIT(referrer_url);
+  VISIT(has_url_keyed_image);
+  VISIT_REP(categories);
+  VISIT_REP(related_searches);
+  VISIT(app_id);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::TrustedVaultAutoUpgradeExperimentGroup& proto) {
+  VISIT(cohort);
+  VISIT_ENUM(type);
+  VISIT(type_index);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::NigoriSpecifics::TrustedVaultDebugInfo& proto) {
+  VISIT(migration_time);
+  VISIT(key_version);
+  VISIT(auto_upgrade_experiment_group);
+  VISIT(auto_upgrade_experiment_group_modification_time_unix_epoch_millis);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::OsPreferenceSpecifics& proto) {
+  VISIT(preference);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::OsPriorityPreferenceSpecifics& proto) {
+  VISIT(preference);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::OutgoingPasswordSharingInvitationSpecifics& proto) {
+  VISIT(guid);
+  VISIT(recipient_user_id);
+  VISIT_BYTES(encrypted_password_sharing_invitation_data);
+  VISIT(client_only_unencrypted_data);
+  VISIT(recipient_key_version);
+  VISIT(sender_key_version);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordSharingInvitationData& proto) {
+  VISIT(password_group_data);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::PasswordSharingInvitationData::PasswordGroupData& proto) {
+  VISIT(username_value);
+  VISIT(password_value);
+  VISIT_REP(element_data);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::PasswordSharingInvitationData::PasswordGroupElementData&
+        proto) {
+  VISIT(scheme);
+  VISIT(signon_realm);
+  VISIT(origin);
+  VISIT(username_element);
+  VISIT(password_element);
+  VISIT(display_name);
+  VISIT(avatar_url);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordSpecifics& proto) {
+  VISIT(encrypted);
+  VISIT(unencrypted_metadata);
+  VISIT(client_only_encrypted_data);
+  VISIT(encrypted_notes_backup);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordSpecificsData& proto) {
+  VISIT(scheme);
+  VISIT(signon_realm);
+  VISIT(origin);
+  VISIT(action);
+  VISIT(username_element);
+  VISIT(username_value);
+  VISIT(password_element);
+  VISIT(password_value);
+  VISIT(preferred);
+  VISIT(date_created);
+  VISIT(blacklisted);
+  VISIT(type);
+  VISIT(times_used);
+  VISIT(display_name);
+  VISIT(avatar_url);
+  VISIT(federation_url);
+  VISIT(date_last_used);
+  VISIT(password_issues);
+  VISIT(date_password_modified_windows_epoch_micros);
+  VISIT(notes);
+  VISIT(sender_email);
+  VISIT(sender_name);
+  VISIT(date_received_windows_epoch_micros);
+  VISIT(sharing_notification_displayed);
+  VISIT(sender_profile_image_url);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordIssues& proto) {
+  VISIT(leaked_password_issue);
+  VISIT(reused_password_issue);
+  VISIT(weak_password_issue);
+  VISIT(phished_password_issue);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordIssues_PasswordIssue& proto) {
+  VISIT(date_first_detection_windows_epoch_micros);
+  VISIT(is_muted);
+  VISIT(trigger_notification_from_backend_on_detection);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordSpecificsData_Notes& proto) {
+  VISIT_REP(note);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordSpecificsData_Notes_Note& proto) {
+  VISIT(unique_display_name);
+  VISIT(value);
+  VISIT(date_created_windows_epoch_micros);
+  VISIT(hide_by_default);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PasswordSpecificsMetadata& proto) {
+  VISIT(url);
+  VISIT(blacklisted);
+  VISIT(date_last_used_windows_epoch_micros);
+  VISIT(password_issues);
+  VISIT(type);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PowerBookmarkSpecifics& proto) {
+  VISIT(guid);
+  VISIT(url);
+  VISIT_ENUM(power_type);
+  VISIT(creation_time_usec);
+  VISIT(update_time_usec);
+  VISIT(power_entity);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PowerEntity& proto) {
+  VISIT(note_entity);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::NoteEntity& proto) {
+  VISIT(plain_text);
+  VISIT(rich_text);
+  VISIT_ENUM(target_type);
+  VISIT(current_note_version);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PersistedEntityData& proto) {
+  VISIT(name);
+  VISIT(specifics);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PlusAddressSettingSpecifics& proto) {
+  VISIT(name);
+  VISIT(bool_value);
+  VISIT(string_value);
+  VISIT(int_value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PlusAddressSpecifics& proto) {
+  VISIT(profile_id);
+  VISIT(facet);
+  VISIT(plus_email);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PlusEmail& proto) {
+  VISIT(email_address);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PreferenceSpecifics& proto) {
+  VISIT(name);
+  VISIT(value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PrinterPPDReference& proto) {
+  VISIT(user_supplied_ppd_url);
+  VISIT(effective_make_and_model);
+  VISIT(autoconf);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PrinterSpecifics& proto) {
+  VISIT(id);
+  VISIT(display_name);
+  VISIT(description);
+  VISIT(manufacturer);
+  VISIT(model);
+  VISIT(uri);
+  VISIT(uuid);
+  VISIT(ppd_reference);
+  VISIT(make_and_model);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PrintersAuthorizationServerSpecifics& proto) {
+  VISIT(uri);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PriorityPreferenceSpecifics& proto) {
+  VISIT(preference);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ReadingListSpecifics& proto) {
+  VISIT(entry_id);
+  VISIT(title);
+  VISIT(url);
+  VISIT(creation_time_us);
+  VISIT(update_time_us);
+  VISIT_ENUM(status);
+  VISIT(first_read_time_us);
+  VISIT(update_title_time_us);
+  VISIT(estimated_read_time_seconds);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SavedTabGroupSpecifics& proto) {
+  VISIT(guid);
+  VISIT(creation_time_windows_epoch_micros);
+  VISIT(update_time_windows_epoch_micros);
+  VISIT(group);
+  VISIT(tab);
+  VISIT(attribution_metadata);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SavedTabGroup& proto) {
+  VISIT(position);
+  VISIT(title);
+  VISIT_ENUM(color);
+  VISIT(pinned_position);
+  VISIT(bookmark_node_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SavedTabGroupTab& proto) {
+  VISIT(position);
+  VISIT(group_guid);
+  VISIT(url);
+  VISIT(title);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AttributionMetadata& proto) {
+  VISIT(created);
+  VISIT(updated);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AttributionMetadata::Attribution& proto) {
+  VISIT(device_info);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::AttributionMetadata::Attribution::AttributionDeviceInfo&
+        proto) {
+  VISIT(cache_guid);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SearchEngineSpecifics& proto) {
+  VISIT(short_name);
+  VISIT(keyword);
+  VISIT(favicon_url);
+  VISIT(url);
+  VISIT(safe_for_autoreplace);
+  VISIT(originating_url);
+  VISIT(date_created);
+  VISIT(input_encodings);
+  VISIT(suggestions_url);
+  VISIT(prepopulate_id);
+  VISIT(autogenerate_keyword);
+  VISIT(last_modified);
+  VISIT(sync_guid);
+  VISIT_REP(alternate_urls);
+  VISIT(image_url);
+  VISIT(search_url_post_params);
+  VISIT(suggestions_url_post_params);
+  VISIT(image_url_post_params);
+  VISIT(new_tab_url);
+  VISIT_ENUM(is_active);
+  VISIT(starter_pack_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SendTabToSelfPush& proto) {
+  VISIT(title);
+  VISIT(text);
+  VISIT_REP(icon);
+  VISIT(favicon);
+  VISIT(destination_url);
+  VISIT(placeholder_title);
+  VISIT(placeholder_body);
+  VISIT(entry_unique_guid);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SendTabToSelfPush::Image& proto) {
+  VISIT(url);
+  VISIT(alt_text);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SendTabToSelfSpecifics& proto) {
+  VISIT(guid);
+  VISIT(title);
+  VISIT(url);
+  VISIT(shared_time_usec);
+  VISIT(device_name);
+  VISIT(target_device_sync_cache_guid);
+  VISIT(opened);
+  VISIT(notification_dismissed);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SessionHeader& proto) {
+  VISIT(session_start_time_unix_epoch_millis);
+  VISIT_REP(window);
+  VISIT(client_name);
+  VISIT_ENUM(device_type);
+  VISIT_ENUM(device_form_factor);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SessionSpecifics& proto) {
+  VISIT(session_tag);
+  VISIT(header);
+  VISIT(tab);
+  VISIT(tab_node_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SessionTab& proto) {
+  VISIT(tab_id);
+  VISIT(window_id);
+  VISIT(tab_visual_index);
+  VISIT(current_navigation_index);
+  VISIT(pinned);
+  VISIT(extension_app_id);
+  VISIT_REP(navigation);
+  VISIT_BYTES(favicon);
+  VISIT_ENUM(favicon_type);
+  VISIT(favicon_source);
+  VISIT_REP(variation_id);
+  VISIT_ENUM(browser_type);
+  VISIT(last_active_time_unix_epoch_millis);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SessionWindow& proto) {
+  VISIT(window_id);
+  VISIT(selected_tab_index);
+  VISIT_REP(tab);
+  VISIT_ENUM(browser_type);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedTabGroup& proto) {
+  VISIT(title);
+  VISIT_ENUM(color);
+  VISIT(originating_tab_group_guid);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedTab& proto) {
+  VISIT(url);
+  VISIT(title);
+  VISIT(shared_tab_group_guid);
+  VISIT(unique_position);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedTabGroupDataSpecifics& proto) {
+  VISIT(guid);
+  VISIT(tab_group);
+  VISIT(tab);
+  VISIT(update_time_windows_epoch_micros);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharingMessageSpecifics& proto) {
+  VISIT(message_id);
+  VISIT(channel_configuration);
+  VISIT_BYTES(payload);
+  VISIT(unencrypted_payload);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharingMessageSpecifics::
+                       ChannelConfiguration::FCMChannelConfiguration& proto) {
+  VISIT(token);
+  VISIT(ttl);
+  VISIT(priority);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharingMessageSpecifics::
+                       ChannelConfiguration::ChimeChannelConfiguration& proto) {
+  VISIT_BYTES(device_token);
+  VISIT_ENUM(channel_type);
+  VISIT(type_id);
+  VISIT(representative_target_id);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::SharingMessageSpecifics::ChannelConfiguration& proto) {
+  VISIT(fcm);
+  VISIT_BYTES(server);
+  VISIT(chime);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SyncCycleCompletedEventInfo& proto) {
+  VISIT(num_encryption_conflicts);
+  VISIT(num_hierarchy_conflicts);
+  VISIT(num_server_conflicts);
+  VISIT(num_updates_downloaded);
+  VISIT(num_reflected_updates_downloaded);
+  VISIT(caller_info);
+  VISIT_ENUM(get_updates_origin);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SyncEntity& proto) {
+  VISIT(id_string);
+  VISIT(parent_id_string);
+  VISIT(version);
+  VISIT(mtime);
+  VISIT(ctime);
+  VISIT(name);
+  VISIT(non_unique_name);
+  VISIT(server_defined_unique_tag);
+  VISIT(unique_position);
+  VISIT(deleted);
+  VISIT(originator_cache_guid);
+  VISIT(originator_client_item_id);
+  VISIT(specifics);
+  VISIT(folder);
+  VISIT(client_tag_hash);
+  VISIT(collaboration);
+  VISIT(deletion_origin);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SyncEntity::CollaborationMetadata& proto) {
+  VISIT(collaboration_id);
+  VISIT(creation_attribution);
+  VISIT(last_update_attribution);
+  VISIT_REP(per_field_attributions);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::SyncEntity::CollaborationMetadata::Attribution& proto) {
+  VISIT(obfuscated_gaia_id);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::SyncEntity::CollaborationMetadata::PerFieldAttribution&
+        proto) {
+  VISIT(attribution_name);
+  VISIT(last_update_obfuscated_gaia_id);
+  VISIT(mtime);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SyncInvalidationsPayload& proto) {
+  VISIT_REP(data_type_invalidations);
+  VISIT_BYTES(hint);
+  VISIT(version);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::SyncInvalidationsPayload::DataTypeInvalidation& proto) {
+  VISIT(data_type_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SecurityEventSpecifics& proto) {
+  VISIT(gaia_password_reuse_event);
+  VISIT(event_time_usec);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::GaiaPasswordReuse& proto) {
+  VISIT(reuse_detected);
+  VISIT(reuse_lookup);
+  VISIT(dialog_interaction);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::GaiaPasswordReuse::PasswordReuseDetected& proto) {
+  VISIT(status);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::GaiaPasswordReuse::PasswordReuseDetected::SafeBrowsingStatus&
+        proto) {
+  VISIT(enabled);
+  VISIT_ENUM(safe_browsing_reporting_population);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::GaiaPasswordReuse::PasswordReuseDialogInteraction& proto) {
+  VISIT_ENUM(interaction_result);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::GaiaPasswordReuse::PasswordReuseLookup& proto) {
+  VISIT_ENUM(lookup_result);
+  VISIT_ENUM(verdict);
+  VISIT(verdict_token);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserDisplayInfo& proto) {
+  VISIT(email);
+  VISIT(display_name);
+  VISIT(profile_image_url);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserInfo& proto) {
+  VISIT(user_id);
+  VISIT(user_display_info);
+  VISIT(cross_user_sharing_public_key);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserEventSpecifics::GaiaPasswordCaptured& proto) {
+  VISIT_ENUM(event_trigger);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserEventSpecifics::FlocIdComputed& proto) {
+  VISIT(floc_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::TabNavigation& proto) {
+  VISIT(virtual_url);
+  VISIT(referrer);
+  VISIT(title);
+  VISIT_ENUM(page_transition);
+  VISIT_ENUM(redirect_type);
+  VISIT(unique_id);
+  VISIT(timestamp_msec);
+  VISIT(navigation_forward_back);
+  VISIT(navigation_from_address_bar);
+  VISIT(navigation_home_page);
+  VISIT(global_id);
+  VISIT(favicon_url);
+  VISIT_ENUM(blocked_state);
+  VISIT(http_status_code);
+  VISIT(obsolete_referrer_policy);
+  VISIT(is_restored);
+  VISIT_REP(navigation_redirect);
+  VISIT(last_navigation_redirect_url);
+  VISIT(correct_referrer_policy);
+  VISIT(page_language);
+  VISIT_ENUM(password_state);
+  VISIT(task_id);
+  VISIT_REP(ancestor_task_id);
+  VISIT(replaced_navigation);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ThemeSpecifics& proto) {
+  VISIT(use_custom_theme);
+  VISIT(use_system_theme_by_default);
+  VISIT(custom_theme_name);
+  VISIT(custom_theme_id);
+  VISIT(custom_theme_update_url);
+  VISIT(autogenerated_color_theme);
+  VISIT(user_color_theme);
+  VISIT(grayscale_theme_enabled);
+  VISIT_ENUM(browser_color_scheme);
+  VISIT(ntp_background);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::ThemeSpecifics::AutogeneratedColorTheme& proto) {
+  VISIT(color);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ThemeSpecificsIos& proto) {
+  VISIT(user_color_theme);
+  VISIT(ntp_background);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserColorTheme& proto) {
+  VISIT(color);
+  VISIT_ENUM(browser_color_variant);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ThemeSpecifics::Empty& proto) {}
+
+VISIT_PROTO_FIELDS(const sync_pb::NtpCustomBackground& proto) {
+  VISIT(url);
+  VISIT(attribution_line_1);
+  VISIT(attribution_line_2);
+  VISIT(attribution_action_url);
+  VISIT(collection_id);
+  VISIT(resume_token);
+  VISIT(refresh_timestamp_unix_epoch_seconds);
+  VISIT(main_color);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::TimeRangeDirective& proto) {
+  VISIT(start_time_usec);
+  VISIT(end_time_usec);
+  VISIT(app_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UrlDirective& proto) {
+  VISIT(url);
+  VISIT(end_time_usec);
+  VISIT(app_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::TypeHint& proto) {
+  VISIT(data_type_id);
+  VISIT(has_valid_hint);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::TypedUrlSpecifics& proto) {
+  VISIT(url);
+  VISIT(title);
+  VISIT(hidden);
+  VISIT_REP(visits);
+  VISIT_REP(visit_transitions);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UnencryptedSharingMessage& proto) {
+  VISIT(sender_guid);
+  VISIT(sender_device_name);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UniquePosition& proto) {
+  VISIT_BYTES(value);
+  VISIT_BYTES(compressed_value);
+  VISIT(uncompressed_length);
+  VISIT_BYTES(custom_compressed_v1);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserConsentSpecifics& proto) {
+  VISIT(locale);
+  VISIT(client_consent_time_usec);
+  VISIT(obfuscated_gaia_id);
+  VISIT(sync_consent);
+  VISIT(arc_backup_and_restore_consent);
+  VISIT(arc_location_service_consent);
+  VISIT(arc_play_terms_of_service_consent);
+  VISIT(assistant_activity_control_consent);
+  VISIT(account_passwords_consent);
+  VISIT(recorder_speaker_label_consent);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserConsentTypes::ArcBackupAndRestoreConsent& proto) {
+  VISIT_REP(description_grd_ids);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserConsentTypes::ArcGoogleLocationServiceConsent& proto) {
+  VISIT_REP(description_grd_ids);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserConsentTypes::ArcPlayTermsOfServiceConsent& proto) {
+  VISIT(play_terms_of_service_text_length);
+  VISIT(play_terms_of_service_hash);
+  VISIT(confirmation_grd_id);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserConsentTypes::AssistantActivityControlConsent& proto) {
+  VISIT(ui_audit_key);
+  VISIT_ENUM(status);
+  VISIT_ENUM(setting_type);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserConsentTypes::SyncConsent& proto) {
+  VISIT_REP(description_grd_ids);
+  VISIT(confirmation_grd_id);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserConsentTypes::UnifiedConsent& proto) {
+  VISIT_REP(description_grd_ids);
+  VISIT(confirmation_grd_id);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserConsentTypes::AccountPasswordsConsent& proto) {
+  VISIT_REP(description_grd_ids);
+  VISIT(confirmation_grd_id);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::UserConsentTypes::RecorderSpeakerLabelConsent& proto) {
+  VISIT_REP(description_grd_ids);
+  VISIT(confirmation_grd_id);
+  VISIT_ENUM(status);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserEventSpecifics& proto) {
+  VISIT(event_time_usec);
+  VISIT(navigation_id);
+  VISIT(session_id);
+  VISIT(test_event);
+  VISIT(gaia_password_reuse_event);
+  VISIT(gaia_password_captured_event);
+  VISIT(floc_id_computed_event);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::UserEventSpecifics::Test& proto) {}
+
+VISIT_PROTO_FIELDS(const sync_pb::CloudTokenData& proto) {
+  VISIT(suffix);
+  VISIT(exp_month);
+  VISIT(exp_year);
+  VISIT(art_fife_url);
+  VISIT(instrument_token);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PaymentInstrument& proto) {
+  VISIT_REP(supported_rails);
+  VISIT(display_icon_url);
+  VISIT(instrument_id);
+  VISIT(bank_account);
+  VISIT(nickname);
+  VISIT(iban);
+  VISIT(ewallet_details);
+  VISIT(device_details);
+  VISIT(bnpl_issuer_details);
+  VISIT_REP(action_required);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PaymentInstrumentCreationOption& proto) {
+  VISIT(id);
+  VISIT(buy_now_pay_later_option);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::BankAccountDetails& proto) {
+  VISIT(bank_name);
+  VISIT(account_number_suffix);
+  VISIT_ENUM(account_type);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::EwalletDetails& proto) {
+  VISIT(ewallet_name);
+  VISIT(account_display_name);
+  VISIT_REP(supported_payment_link_uris);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::DeviceDetails& proto) {
+  VISIT(is_fido_enrolled);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CardBenefit& proto) {
+  VISIT(benefit_id);
+  VISIT(benefit_description);
+  VISIT(start_time_unix_epoch_milliseconds);
+  VISIT(end_time_unix_epoch_milliseconds);
+  VISIT(flat_rate_benefit);
+  VISIT(category_benefit);
+  VISIT(merchant_benefit);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CardBenefit_FlatRateBenefit& proto) {}
+
+VISIT_PROTO_FIELDS(const sync_pb::CardBenefit_CategoryBenefit& proto) {
+  VISIT_ENUM(category_benefit_type);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CardBenefit_MerchantBenefit& proto) {
+  VISIT_REP(merchant_domain);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CardIssuer& proto) {
+  VISIT_ENUM(issuer);
+  VISIT(issuer_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WalletMaskedCreditCard& proto) {
+  VISIT(id);
+  VISIT_ENUM(status);
+  VISIT(name_on_card);
+  VISIT_ENUM(type);
+  VISIT(last_four);
+  VISIT(exp_month);
+  VISIT(exp_year);
+  VISIT(billing_address_id);
+  VISIT(bank_name);
+  VISIT(nickname);
+  VISIT(card_issuer);
+  VISIT(instrument_id);
+  VISIT_ENUM(virtual_card_enrollment_state);
+  VISIT(card_art_url);
+  VISIT(product_description);
+  VISIT_ENUM(virtual_card_enrollment_type);
+  VISIT_REP(card_benefit);
+  VISIT(product_terms_url);
+  VISIT_ENUM(card_info_retrieval_enrollment_state);
+  VISIT_ENUM(card_benefit_source);
+  VISIT_ENUM(card_creation_source);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WalletMetadataSpecifics& proto) {
+  VISIT_ENUM(type);
+  VISIT(id);
+  VISIT(use_count);
+  VISIT(use_date);
+  VISIT(card_billing_address_id);
+  VISIT(address_has_converted);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WalletPostalAddress& proto) {
+  VISIT(id);
+  VISIT(recipient_name);
+  VISIT(company_name);
+  VISIT_REP(street_address);
+  VISIT(address_1);
+  VISIT(address_2);
+  VISIT(address_3);
+  VISIT(address_4);
+  VISIT(postal_code);
+  VISIT(sorting_code);
+  VISIT(country_code);
+  VISIT(phone_number);
+  VISIT(language_code);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::PaymentsCustomerData& proto) {
+  VISIT(id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WalletCreditCardCloudTokenData& proto) {
+  VISIT(masked_card_id);
+  VISIT(suffix);
+  VISIT(exp_month);
+  VISIT(exp_year);
+  VISIT(art_fife_url);
+  VISIT(instrument_token);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WalletMaskedIban& proto) {
+  VISIT(instrument_id);
+  VISIT(prefix);
+  VISIT(suffix);
+  VISIT(length);
+  VISIT(nickname);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WebApkIconInfo& proto) {
+  VISIT(size_in_px);
+  VISIT(url);
+  VISIT_ENUM(purpose);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WebApkSpecifics& proto) {
+  VISIT(manifest_id);
+  VISIT(start_url);
+  VISIT(name);
+  VISIT(theme_color);
+  VISIT(scope);
+  VISIT_REP(icon_infos);
+  VISIT(last_used_time_windows_epoch_micros);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WebAppIconInfo& proto) {
+  VISIT(size_in_px);
+  VISIT(url);
+  VISIT_ENUM(purpose);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WebAppSpecifics& proto) {
+  VISIT(start_url);
+  VISIT(name);
+  VISIT_ENUM(user_display_mode_default);
+  VISIT(theme_color);
+  VISIT(scope);
+  VISIT_REP(icon_infos);
+  VISIT(user_page_ordinal);
+  VISIT(user_launch_ordinal);
+  VISIT(relative_manifest_id);
+  VISIT_ENUM(user_display_mode_cros);
+  VISIT_REP(trusted_icons);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WifiConfigurationSpecifics::
+                       ProxyConfiguration::ManualProxyConfiguration& proto) {
+  VISIT(http_proxy_url);
+  VISIT(http_proxy_port);
+  VISIT(secure_http_proxy_url);
+  VISIT(secure_http_proxy_port);
+  VISIT(socks_host_url);
+  VISIT(socks_host_port);
+  VISIT_REP(excluded_domains);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::WifiConfigurationSpecifics::ProxyConfiguration& proto) {
+  VISIT_ENUM(proxy_option);
+  VISIT(autoconfiguration_url);
+  VISIT(manual_proxy_configuration);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WifiConfigurationSpecifics& proto) {
+  VISIT_BYTES(hex_ssid);
+  VISIT_ENUM(security_type);
+  VISIT_BYTES(passphrase);
+  VISIT_ENUM(automatically_connect);
+  VISIT_ENUM(is_preferred);
+  VISIT(proxy_configuration);
+  VISIT_REP(custom_dns);
+  VISIT(last_connected_timestamp);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics& proto) {
+  VISIT(uuid);
+  VISIT(name);
+  VISIT(created_time_windows_epoch_micros);
+  VISIT(updated_time_windows_epoch_micros);
+  VISIT(desk);
+  VISIT_ENUM(desk_type);
+  VISIT(client_cache_guid);
+  VISIT_ENUM(device_form_factor);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics::App& proto) {
+  VISIT(window_bound);
+  VISIT_ENUM(window_state);
+  VISIT(z_index);
+  VISIT(app);
+  VISIT(window_id);
+  VISIT(display_id);
+  VISIT_ENUM(pre_minimized_window_state);
+  VISIT(snap_percentage);
+  VISIT_ENUM(container);
+  VISIT_ENUM(disposition);
+  VISIT(app_name);
+  VISIT(title);
+  VISIT(override_url);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics::AppOneOf& proto) {
+  VISIT(browser_app_window);
+  VISIT(chrome_app);
+  VISIT(progress_web_app);
+  VISIT(arc_app);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::WorkspaceDeskSpecifics::BrowserAppWindow& proto) {
+  VISIT_REP(tabs);
+  VISIT(active_tab_index);
+  VISIT(show_as_app);
+  VISIT_REP(tab_groups);
+  VISIT(first_non_pinned_tab_index);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::WorkspaceDeskSpecifics::BrowserAppWindow::BrowserAppTab&
+        proto) {
+  VISIT(url);
+  VISIT(title);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics::ChromeApp& proto) {
+  VISIT(app_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics::Desk& proto) {
+  VISIT_REP(apps);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::WorkspaceDeskSpecifics::ProgressiveWebApp& proto) {
+  VISIT(app_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics::WindowBound& proto) {
+  VISIT(top);
+  VISIT(left);
+  VISIT(width);
+  VISIT(height);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::WorkspaceDeskSpecifics::ArcApp& proto) {
+  VISIT(app_id);
+  VISIT(minimum_size);
+  VISIT(maximum_size);
+  VISIT(bounds_in_root);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::WorkspaceDeskSpecifics::ArcApp::WindowSize& proto) {
+  VISIT(width);
+  VISIT(height);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::WorkspaceDeskSpecifics::BrowserAppWindow::TabGroup& proto) {
+  VISIT(first_index);
+  VISIT(last_index);
+  VISIT(title);
+  VISIT_ENUM(color);
+  VISIT(is_collapsed);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::Any& proto) {
+  VISIT_REP(type_url);
+  VISIT_REP(value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillValuableSpecifics& proto) {
+  VISIT(id);
+  VISIT(is_editable);
+  VISIT(loyalty_card);
+  VISIT(vehicle_registration);
+  VISIT(flight_reservation);
+  VISIT(serialized_chrome_valuables_metadata);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::LoyaltyCard& proto) {
+  VISIT(merchant_name);
+  VISIT(program_name);
+  VISIT(program_logo);
+  VISIT(loyalty_card_number);
+  VISIT_REP(merchant_domains);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::VehicleRegistration& proto) {
+  VISIT(vehicle_make);
+  VISIT(vehicle_model);
+  VISIT(vehicle_year);
+  VISIT(vehicle_identification_number);
+  VISIT(vehicle_license_plate);
+  VISIT(license_plate_region);
+  VISIT(license_plate_country);
+  VISIT(owner_name);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::FlightReservation& proto) {
+  VISIT(flight_number);
+  VISIT(flight_ticket_number);
+  VISIT(flight_confirmation_code);
+  VISIT(passenger_name);
+  VISIT(departure_airport);
+  VISIT(arrival_airport);
+  VISIT(departure_date_unix_epoch_micros);
+  VISIT(arrival_date_unix_epoch_micros);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::AutofillValuableSettingSpecifics& proto) {
+  VISIT(name);
+  VISIT(bool_value);
+  VISIT(string_value);
+  VISIT(int_value);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedTabDetails& proto) {
+  VISIT(shared_tab_group_guid);
+  VISIT(last_seen_timestamp_windows_epoch);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedTabGroupDetails& proto) {
+  VISIT(pinned_position);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedTabGroupAccountDataSpecifics& proto) {
+  VISIT(guid);
+  VISIT(collaboration_id);
+  VISIT(shared_tab_details);
+  VISIT(shared_tab_group_details);
+  VISIT(update_time_windows_epoch_micros);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::CommentData::Attribution::CommentTarget::FragmentLink&
+        proto) {
+  VISIT(fragment);
+  VISIT(text_preview);
+}
+
+VISIT_PROTO_FIELDS(
+    const sync_pb::CommentData::Attribution::CommentTarget& proto) {
+  VISIT(shared_url_context_uuid);
+  VISIT(link_fragment);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommentData::Attribution::InReplyTo& proto) {
+  VISIT(parent_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommentData::Attribution& proto) {
+  VISIT(top_level);
+  VISIT(parent);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommentData::OrderKey& proto) {
+  VISIT(device_guid);
+  VISIT(local_sequence);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::CommentData& proto) {
+  VISIT(text);
+  VISIT(attribution);
+  VISIT(order_key);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedUrlContext::UrlRepresentation& proto) {
+  VISIT_ENUM(source);
+  VISIT(value);
+  VISIT(version);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedUrlContext& proto) {
+  VISIT_REP(representations);
+  VISIT(title);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::SharedCommentSpecifics& proto) {
+  VISIT(uuid);
+  VISIT(context_id);
+  VISIT(proto_version);
+  VISIT(comment);
+  VISIT(shared_url_context);
+}
+
+}  // namespace syncer
+
+#undef VISIT_
+#undef VISIT_BYTES
+#undef VISIT_ENUM
+#undef VISIT
+#undef VISIT_REP
+
+#endif  // COMPONENTS_SYNC_PROTOCOL_PROTO_VISITORS_H_
diff --git a/pyhindsight/lib/components/sync/protocol/protocol_sources.gni b/pyhindsight/lib/components/sync/protocol/protocol_sources.gni
new file mode 100644
index 0000000..004c087
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/protocol_sources.gni
@@ -0,0 +1,90 @@
+# Copyright 2015 The Chromium Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+sync_protocol_sources = [
+  "app_list_specifics.proto",
+  "app_setting_specifics.proto",
+  "app_specifics.proto",
+  "arc_package_specifics.proto",
+  "autofill_offer_specifics.proto",
+  "autofill_specifics.proto",
+  "autofill_valuable_setting_specifics.proto",
+  "autofill_valuable_specifics.proto",
+  "autofill_wallet_credential_specifics.proto",
+  "autofill_wallet_usage_specifics.proto",
+  "bookmark_model_metadata.proto",
+  "bookmark_specifics.proto",
+  "client_commands.proto",
+  "client_debug_info.proto",
+  "collaboration_group_metadata.proto",
+  "collaboration_group_specifics.proto",
+  "contact_info_specifics.proto",
+  "cookie_specifics.proto",
+  "data_type_progress_marker.proto",
+  "data_type_state.proto",
+  "data_type_store_schema_descriptor.proto",
+  "deletion_origin.proto",
+  "device_info_specifics.proto",
+  "dictionary_specifics.proto",
+  "encryption.proto",
+  "entity_metadata.proto",
+  "entity_specifics.proto",
+  "extension_setting_specifics.proto",
+  "extension_specifics.proto",
+  "gaia_password_reuse.proto",
+  "get_updates_caller_info.proto",
+  "history_delete_directive_specifics.proto",
+  "history_specifics.proto",
+  "history_status.proto",
+  "loopback_server.proto",
+  "managed_user_setting_specifics.proto",
+  "managed_user_shared_setting_specifics.proto",
+  "nigori_local_data.proto",
+  "nigori_specifics.proto",
+  "note_entity.proto",
+  "os_preference_specifics.proto",
+  "os_priority_preference_specifics.proto",
+  "password_sharing_invitation_specifics.proto",
+  "password_sharing_recipients.proto",
+  "password_specifics.proto",
+  "persisted_entity_data.proto",
+  "plus_address_setting_specifics.proto",
+  "plus_address_specifics.proto",
+  "power_bookmark_specifics.proto",
+  "preference_specifics.proto",
+  "printer_specifics.proto",
+  "printers_authorization_server_specifics.proto",
+  "priority_preference_specifics.proto",
+  "product_comparison_specifics.proto",
+  "reading_list_specifics.proto",
+  "saved_tab_group_specifics.proto",
+  "search_engine_specifics.proto",
+  "security_event_specifics.proto",
+  "send_tab_to_self_specifics.proto",
+  "session_specifics.proto",
+  "shared_comment_specifics.proto",
+  "shared_tab_group_account_data_specifics.proto",
+  "shared_tab_group_data_specifics.proto",
+  "sharing_message_specifics.proto",
+  "sync.proto",
+  "sync_entity.proto",
+  "sync_enums.proto",
+  "sync_invalidations_payload.proto",
+  "tab_group_attribution_metadata.proto",
+  "test.proto",
+  "theme_specifics.proto",
+  "theme_specifics_ios.proto",
+  "theme_types.proto",
+  "typed_url_specifics.proto",
+  "unencrypted_sharing_message.proto",
+  "unique_position.proto",
+  "user_consent_specifics.proto",
+  "user_consent_types.proto",
+  "user_event_specifics.proto",
+  "web_apk_specifics.proto",
+  "web_app_specifics.proto",
+  "webauthn_credential_specifics.proto",
+  "wifi_configuration_specifics.proto",
+  "workspace_desk_specifics.proto",
+]
diff --git a/pyhindsight/lib/components/sync/protocol/reading_list_specifics.proto b/pyhindsight/lib/components/sync/protocol/reading_list_specifics.proto
new file mode 100644
index 0000000..5728871
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/reading_list_specifics.proto
@@ -0,0 +1,46 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for the reading list items.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Sync Reading list entry. This proto contains the fields synced for a reading
+// list entry. It must be kept synced with the reading_list.ReadingListLocal
+// protobuf.
+message ReadingListSpecifics {
+  // entry_id and url must be equal.
+  optional string entry_id = 1;
+  optional string title = 2;
+  optional string url = 3;
+
+  // The timestamps are microseconds since the unix epoch.
+  // TODO(crbug.com/353449026): Consider renaming the fields to use the
+  // preferred naming scheme, i.e. `_unix_epoch_micros`.
+  optional int64 creation_time_us = 4;
+  optional int64 update_time_us = 5;
+  optional int64 first_read_time_us = 7;
+  optional int64 update_title_time_us = 8;
+
+  optional int32 estimated_read_time_seconds = 9;
+
+  enum ReadingListEntryStatus {
+    UNREAD = 0;
+    READ = 1;
+    UNSEEN = 2;
+  }
+
+  // If the field is not present, it defaults to UNSEEN.
+  optional ReadingListEntryStatus status = 6;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/saved_tab_group_specifics.proto b/pyhindsight/lib/components/sync/protocol/saved_tab_group_specifics.proto
new file mode 100644
index 0000000..862e664
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/saved_tab_group_specifics.proto
@@ -0,0 +1,109 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/tab_group_attribution_metadata.proto";
+
+// LINT.IfChange(SavedTabGroupSpecifics)
+// Sync protocol datatype extension for saved tab groups. Saved Tab Groups are
+// tab groups which can be recalled between browser sessions, and if sync is
+// turned on, cross device. A saved tab group contains tabs which are stored as
+// a SavedTabGroupSpecifics separately (SavedTabGroupTab). This is due to
+// limitations from the sync service on the size of an individual sync entity.
+message SavedTabGroup {
+  // These colors map to tab_groups::TabGroupColorId. They DO NOT match the enum
+  // integer values due to "kGrey" being in the "Unspecified" field.
+  enum SavedTabGroupColor {
+    SAVED_TAB_GROUP_COLOR_UNSPECIFIED = 0;
+    SAVED_TAB_GROUP_COLOR_GREY = 1;
+    SAVED_TAB_GROUP_COLOR_BLUE = 2;
+    SAVED_TAB_GROUP_COLOR_RED = 3;
+    SAVED_TAB_GROUP_COLOR_YELLOW = 4;
+    SAVED_TAB_GROUP_COLOR_GREEN = 5;
+    SAVED_TAB_GROUP_COLOR_PINK = 6;
+    SAVED_TAB_GROUP_COLOR_PURPLE = 7;
+    SAVED_TAB_GROUP_COLOR_CYAN = 8;
+    SAVED_TAB_GROUP_COLOR_ORANGE = 9;
+  }
+
+  // The position of the SavedTabGroup in any visual display. This also
+  // represents the index in the SavedTabGroupModel of the group. This field
+  // will be deprecated and replaced by the pinned_position field in tab group
+  // V2.
+  optional int64 position = 1;
+
+  // The displayed title of the group, shown on the tab group and the saved tab
+  // group button.
+  optional string title = 2;
+
+  // The color of the group, mapped to tab_groups::TabGroupColorId.
+  optional SavedTabGroupColor color = 3;
+
+  // Position of the pinned tab group in bookmark bar on Desktop. This will
+  // replace the position field in Tab Group V2.
+  optional int64 pinned_position = 4;
+
+  reserved 5;
+
+  // The guid of a bookmark node. This is used for associating a bookmark
+  // folder with a tab group by bookmarks tab group conversion.
+  optional string bookmark_node_id = 6;
+}
+
+// Sync protocol datatype extension for saved tab group tabs. SavedTabGroupTab
+// are the sync representation of a tab in a saved tab group. they are stored as
+// separate entities due to size limitations of sync entities.
+message SavedTabGroupTab {
+  // An id that links the saved tab group tab to it's saved tab group.
+  optional string group_guid = 1;
+
+  // The position in the Tab Strip the tab is located relative to the start of
+  // the tab group. This is also the index in the saved_tabs_ vector in the
+  // SavedTabGroup in the SavedTabGroupModel, which is updated by the
+  // TabStripModel.
+  optional int64 position = 2;
+
+  // Tab Data used for constructing the tab.
+  optional string url = 3;
+
+  // The displayed title of the tab, shown on the saved tab group button's
+  // context menu.
+  optional string title = 4;
+}
+
+message SavedTabGroupSpecifics {
+  // An id that refers to the sync saved tab group object.
+  optional string guid = 1;
+
+  // Timestamps for CRUD operations.
+  optional int64 creation_time_windows_epoch_micros = 2;
+  optional int64 update_time_windows_epoch_micros = 3;
+
+  oneof entity {
+    SavedTabGroup group = 4;
+    SavedTabGroupTab tab = 5;
+  }
+
+  // Attribution metadata about the associated tab group or tab.
+  optional AttributionMetadata attribution_metadata = 6;
+
+  // A mechanism to identify the client version that wrote this specifics.
+  // Designed to aid business logic when reading newly added fields that
+  // didn't exist in older clients.
+  // The client version must be incremented whenever a new field is added to the
+  // specifics.
+  optional int32 version = 7;
+}
+// LINT.ThenChange(//components/saved_tab_groups/internal/saved_tab_group_sync_bridge.cc:TrimAllSupportedFieldsFromRemoteSpecifics)
diff --git a/pyhindsight/lib/components/sync/protocol/search_engine_specifics.proto b/pyhindsight/lib/components/sync/protocol/search_engine_specifics.proto
new file mode 100644
index 0000000..aff67cc
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/search_engine_specifics.proto
@@ -0,0 +1,96 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for custom search engines.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+// Fields that are not used anymore should be marked [deprecated = true].
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of custom search engine sync objects.
+message SearchEngineSpecifics {
+  // The description of the search engine.
+  optional string short_name = 1;
+  // The search engine keyword for omnibox access.
+  optional string keyword = 2;
+  // A URL to the favicon to show in the search engines options page.
+  optional string favicon_url = 3;
+  // The actual parameterized search engine query URL.
+  optional string url = 4;
+  // A flag signifying whether it is safe to automatically modify this search
+  // engine entry or not.
+  optional bool safe_for_autoreplace = 5;
+  // The URL to the OSD file this search engine entry came from.
+  optional string originating_url = 6;
+  // The date this search engine entry was created. A UTC timestamp with units
+  // in microseconds.
+  optional int64 date_created = 7;
+  // A list of supported input encodings.
+  optional string input_encodings = 8;
+  // Obsolete field. This used to represent whether or not this entry is shown
+  // in the list of default search engines.
+  optional bool deprecated_show_in_default_list = 9 [deprecated = true];
+  // The parameterized URL that provides suggestions as the user types.
+  optional string suggestions_url = 10;
+  // The ID associated with the prepopulate data this search engine comes from.
+  // Set to zero if it was not prepopulated.
+  optional int32 prepopulate_id = 11;
+  // DEPRECATED: Whether to autogenerate a keyword for the search engine or not.
+  // Do not write to this field in the future.  We preserve this for now so we
+  // can read the field in order to migrate existing data that sets this bit.
+  optional bool autogenerate_keyword = 12 [deprecated = true];
+  // ID 13 reserved - previously used by `logo_id`, now deprecated.
+  optional string instant_url = 15 [deprecated = true];
+  // ID 16 reserved - previously used by `id`, now deprecated.
+  // The last time this entry was modified by a user. A UTC timestamp with units
+  // in microseconds.
+  optional int64 last_modified = 17;
+  // The primary identifier of this search engine entry for Sync.
+  optional string sync_guid = 18;
+  // A list of URL patterns that can be used, in addition to `url`, to extract
+  // search terms from a URL.
+  repeated string alternate_urls = 19;
+  optional string search_terms_replacement_key = 20 [deprecated = true];
+  // The parameterized URL that provides image results according to the image
+  // content or image URL provided by user.
+  optional string image_url = 21;
+
+  // The following post_params are comma-separated lists used to specify the
+  // post parameters for the corresponding search URL.
+  optional string search_url_post_params = 22;
+  optional string suggestions_url_post_params = 23;
+  optional string instant_url_post_params = 24 [deprecated = true];
+  optional string image_url_post_params = 25;
+
+  // The parameterized URL for a search provider specified new tab page.
+  optional string new_tab_url = 26;
+
+  enum ActiveStatus {
+    // The default state when a SE is auto-added. Unspecified SE are inactive.
+    ACTIVE_STATUS_UNSPECIFIED = 0;
+    // The SE is active and can be triggered via the omnibox.
+    ACTIVE_STATUS_TRUE = 1;
+    // The SE has been manually set to inactive by the user.
+    ACTIVE_STATUS_FALSE = 2;
+  }
+  // Whether a search engine is 'active' and can be triggered via the omnibox by
+  // typing in the relevant keyword.
+  optional ActiveStatus is_active = 27;
+  // The ID associated with the starter pack engine.  This is set to 0 if not a
+  // starter pack engine.
+  optional int32 starter_pack_id = 28;
+
+  reserved 14;
+  reserved "created_by_policy";
+}
diff --git a/pyhindsight/lib/components/sync/protocol/security_event_specifics.proto b/pyhindsight/lib/components/sync/protocol/security_event_specifics.proto
new file mode 100644
index 0000000..f29ab7e
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/security_event_specifics.proto
@@ -0,0 +1,27 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for security events.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/gaia_password_reuse.proto";
+
+message SecurityEventSpecifics {
+  // The specific security event to record.
+  oneof event { GaiaPasswordReuse gaia_password_reuse_event = 1; }
+
+  // Time of event, as measured by client in microseconds since Windows epoch.
+  optional int64 event_time_usec = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/send_tab_to_self_specifics.proto b/pyhindsight/lib/components/sync/protocol/send_tab_to_self_specifics.proto
new file mode 100644
index 0000000..d0026b6
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/send_tab_to_self_specifics.proto
@@ -0,0 +1,45 @@
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for the reading list items.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Send Tab To Self list entry. This proto contains the fields synced to send
+// a url across devices.
+message SendTabToSelfSpecifics {
+  // A random unique identifier for each shared tab.
+  // Required.
+  optional string guid = 5;
+  // The name of the tab being shared.
+  optional string title = 1;
+  // The URL of the tab being shared.
+  // Required.
+  optional string url = 2;
+  // The time the tab was shared as measured by the client in microseconds since
+  // the windows epoch.
+  optional int64 shared_time_usec = 3;
+  // A non-unique but human readable name to describe this client, used in UI.
+  optional string device_name = 4;
+  // The stable Device_id of the device that this tab was shared with.
+  // Required.
+  optional string target_device_sync_cache_guid = 7;
+  // A boolean to designate if the shared tab been opened on the target device.
+  optional bool opened = 8;
+  // Whether the notification for this proto been dismissed.
+  optional bool notification_dismissed = 9;
+
+  reserved "navigation_time_usec";
+  reserved 6;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/session_specifics.proto b/pyhindsight/lib/components/sync/protocol/session_specifics.proto
new file mode 100644
index 0000000..ac693b9
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/session_specifics.proto
@@ -0,0 +1,202 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for sessions.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/sync_enums.proto";
+
+message SessionSpecifics {
+  // Unique id for the client. M89 and higher use sync's cache GUID (client ID)
+  // to populate this tag for *new* sessions.
+  optional string session_tag = 1;
+  optional SessionHeader header = 2;
+  optional SessionTab tab = 3;
+
+  // The local tab id used by sync. Unique across all nodes for that client.
+  optional int32 tab_node_id = 4 [default = -1];
+}
+
+// Properties of session sync objects.
+message SessionHeader {
+  // The timestamp when this session was started, i.e. when the user signed in
+  // or turned on the sessions data type. Introduced in M130, and not populated
+  // for sessions created/started before that milestone.
+  optional int64 session_start_time_unix_epoch_millis = 6;
+  // Each session is composed of windows.
+  repeated SessionWindow window = 2;
+  // A non-unique but human-readable name to describe this client.
+  optional string client_name = 3;
+  // The form factor of device.
+  optional SyncEnums.DeviceFormFactor device_form_factor = 5;
+
+  // The type of device.
+  // Mandatory until M115. Replaced by device_form_factor afterwards, but still
+  // populated for backward compatibility.
+  optional SyncEnums.DeviceType device_type = 4 [deprecated = true];
+}
+
+message SessionWindow {
+  // Unique (to the owner) id for this window.
+  optional int32 window_id = 1;
+  // Index of the selected tab in tabs; -1 if no tab is selected.
+  optional int32 selected_tab_index = 2 [default = -1];
+  // Type of the window.
+  optional SyncEnums.BrowserType browser_type = 3 [default = TYPE_TABBED];
+  // The tabs that compose a window (correspond to tab id's).
+  repeated int32 tab = 4;
+}
+
+message SessionTab {
+  // Unique (to the owner) id for this tab.
+  optional int32 tab_id = 1 [default = -1];
+  // The unique id for the window this tab belongs to.
+  optional int32 window_id = 2;
+  // Visual index of the tab within its window. There may be gaps in these
+  // values.
+  optional int32 tab_visual_index = 3 [default = -1];
+  // Identifies the index of the current navigation in navigations. For
+  // example, if this is 2 it means the current navigation is navigations[2].
+  optional int32 current_navigation_index = 4 [default = -1];
+  // True if the tab is pinned.
+  optional bool pinned = 5 [default = false];
+  // If non-empty, this tab is an app tab and this is the id of the extension.
+  optional string extension_app_id = 6;
+  // Tabs are navigated, and the navigation data is here.
+  repeated TabNavigation navigation = 7;
+
+  optional SyncEnums.BrowserType browser_type = 13;
+
+  // Timestamp for when this tab was last activated.
+  // Corresponds to WebContents::GetLastActiveTime().
+  optional int64 last_active_time_unix_epoch_millis = 14;
+
+  // The favicon for the current url the tab is displaying. Either empty
+  // or a valid PNG encoded favicon.
+  optional bytes favicon = 8 [deprecated = true];
+  // The type of favicon. For now only normal web favicons are supported.
+  enum FaviconType { TYPE_WEB_FAVICON = 1; }
+  optional FaviconType favicon_type = 9 [deprecated = true];
+  // The url of the actual favicon (as opposed to the page using the favicon).
+  optional string favicon_source = 11 [deprecated = true];
+  // Ids of the currently assigned variations which should be sent to sync.
+  repeated uint64 variation_id = 12 [deprecated = true];
+}
+
+message TabNavigation {
+  // The page's URL as displayed to the user (which can be the actual page URL
+  // or a virtual override). It can be empty or, in rare cases, an unsyncable
+  // URL, so it is the receiver's responsibility to implement additional
+  // filtering before displaying these URLs or tabs in the UI.
+  optional string virtual_url = 2;
+  // The referring URL, which can be empty.
+  optional string referrer = 3;
+  // The title of the page.
+  optional string title = 4;
+  // The core transition type.
+  optional SyncEnums.PageTransition page_transition = 6 [default = LINK];
+  // If this transition was triggered by a redirect, the redirect type.
+  optional SyncEnums.PageTransitionRedirectType redirect_type = 7;
+  // The unique navigation id (within this client).
+  optional int32 unique_id = 8;
+  // Timestamp for when this navigation last occurred (in client time).
+  // If the user goes back/forward in history the timestamp may refresh.
+  optional int64 timestamp_msec = 9;
+  // User used the Forward or Back button to navigate among browsing history.
+  optional bool navigation_forward_back = 10;
+  // User used the address bar to trigger this navigation.
+  optional bool navigation_from_address_bar = 11;
+  // User is navigating to the home page.
+  optional bool navigation_home_page = 12;
+  // The id for this navigation, which is globally unique with high
+  // probability.
+  optional int64 global_id = 15;
+  // The favicon url associated with this page.
+  optional string favicon_url = 17;
+
+  // The status code from the last navigation.
+  optional int32 http_status_code = 20;
+
+  // Correct referrer policy. Valid enums are defined in
+  // third_party/WebKit/public/platform/WebReferrerPolicy.h.
+  optional int32 correct_referrer_policy = 25 [default = 1];
+
+  // Whether the Password Manager saw a password field on the page.
+  optional SyncEnums.PasswordState password_state = 26;
+
+  // The start/end of a redirect chain. Deprecated in M108 because they were
+  // always set to false in practice, and don't make sense in the first place -
+  // this message corresponds to a complete chain.
+  optional bool navigation_chain_start = 13 [deprecated = true];
+  optional bool navigation_chain_end = 14 [deprecated = true];
+  // Search terms extracted from the URL. Deprecated in M64.
+  optional string search_terms = 16 [deprecated = true];
+  enum BlockedState {
+    STATE_ALLOWED = 1;
+    STATE_BLOCKED = 2;
+  }
+  // Whether access to the URL was allowed or blocked. Deprecated in M121
+  // because it was unused.
+  optional BlockedState blocked_state = 18
+      [deprecated = true, default = STATE_ALLOWED];
+  // Referrer policy. Old, broken value. Deprecated in M61.
+  optional int32 obsolete_referrer_policy = 21 [deprecated = true];
+  // True if created from restored navigation entry that hasn't been loaded.
+  // Deprecated in M121 because it was unused.
+  optional bool is_restored = 22 [deprecated = true];
+  // The chain of redirections for this navigation, from the original URL
+  // through the last URL that redirected. Deprecated in M121 because it was
+  // unused.
+  repeated NavigationRedirect navigation_redirect = 23 [deprecated = true];
+  // The last URL traversed when different from the virtual_url. Deprecated in
+  // M121 because it was unused.
+  optional string last_navigation_redirect_url = 24 [deprecated = true];
+  // The id for the task associated with this navigation, which is globally
+  // unique with high probability. Deprecated in M121 because it was unused.
+  optional int64 task_id = 27 [deprecated = true];
+  // Task ids of all ancestor navigations, which can be from other tabs, from
+  // root to parent. Deprecated in M121 because it was unused.
+  repeated int64 ancestor_task_id = 28 [deprecated = true];
+  // When a history entry is replaced (e.g. history.replaceState()), this
+  // contained some information about the entry prior to being replaced.
+  // Deprecated in M121 because it was unused.
+  optional ReplacedNavigation replaced_navigation = 29 [deprecated = true];
+  // The page language as determined by its textual content. An ISO 639 language
+  // code (two letters, except for Chinese where a localization is necessary).
+  // Deprecated in M121 because it was unused.
+  optional string page_language = 30 [deprecated = true];
+
+  reserved 1;
+  reserved "index";
+  reserved 5;
+  reserved "state";
+  reserved 19;
+  reserved "content_pack_categories";
+}
+
+// Navigation information for a single redirection within a single navigation.
+message NavigationRedirect {
+  // A URL that redirected while navigating to the virtual_url.
+  optional string url = 1;
+}
+
+// Subset of TabNavigation fields representing a navigation that was later
+// replaced in history (e.g. history.replaceState()), which allows tracking
+// information about the original navigation prior to the first replacement.
+message ReplacedNavigation {
+  optional string first_committed_url = 1;
+  optional int64 first_timestamp_msec = 2;
+  optional SyncEnums.PageTransition first_page_transition = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/shared_comment_specifics.proto b/pyhindsight/lib/components/sync/protocol/shared_comment_specifics.proto
new file mode 100644
index 0000000..e524a40
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/shared_comment_specifics.proto
@@ -0,0 +1,141 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Represents the context of a URL shared within a group, including its various
+// representations and metadata.
+message SharedUrlContext {
+  enum Source {
+    // The source is not specified.
+    SOURCE_UNSPECIFIED = 0;
+    // The current URL shown in the Omnibox.
+    OMNIBOX = 1;
+    // The URL we received or sent through Chrome Sync.
+    FROM_SYNC = 2;
+    // The Canonical URL the client identified.
+    CANONICAL_URL = 3;
+  }
+
+  // A specific representation of a URL from a particular source.
+  message UrlRepresentation {
+    // Where this URL representation was received from.
+    optional Source source = 1;
+    // The URL, hash, or other unique identifier for this representation.
+    optional string value = 2;
+    // An optional version string to differentiate representations over time.
+    optional string version = 3;
+  }
+
+  // A list of all known representations for this URL. This allows different
+  // clients to find a common representation for identifying the page.
+  repeated UrlRepresentation representations = 1;
+
+  // The title of the web page this SharedUrlContext refers to.
+  optional string title = 2;
+}
+
+// Contains all the data for a user-authored comment, including its
+// content, sorting key, and attribution.
+message CommentData {
+  // The user-authored comment string, which may contain rich text.
+  optional string text = 1;
+
+  // Describes what a comment is about, such as a reply to another comment or a
+  // new comment on a specific target.
+  message Attribution {
+    // Identifies the target of a top-level comment.
+    message CommentTarget {
+      // The UUID of the `SharedUrlContext` specifics this comment is attached
+      // to.
+      optional string shared_url_context_uuid = 1;
+
+      // A link to a specific text fragment within the page (i.e., a "deep
+      // link").
+      message FragmentLink {
+        // The fragment part of the link, i.e. the #:~:text=... part of the
+        // link.
+        optional string fragment = 1;
+        // A string representation of the selected text to be used in previews.
+        optional string text_preview = 2;
+      }
+      // An optional link to a text fragment within the page.
+      optional FragmentLink link_fragment = 2;
+    }
+
+    // Identifies the parent comment this comment is a reply to.
+    message InReplyTo {
+      // The UUID of the parent comment.
+      optional string parent_id = 1;
+    }
+
+    // Defines whether the comment is a new thread or a reply.
+    oneof kind {
+      // The target if this is a new top-level comment.
+      CommentTarget top_level = 1;
+      // Metadata about the parent comment if this is a reply.
+      InReplyTo parent = 2;
+    }
+  }
+
+  // The attribution data for this comment, indicating what it refers to.
+  optional Attribution attribution = 2;
+
+  // Defines a key used for deterministically sorting comments in a distributed
+  // system. This ensures that all clients render comments in the same stable
+  // order, regardless of network timing or processing order. This is intended
+  // to be used together with the creation time of an entity to provide a
+  // strictly monotonically increasing ordering.
+  message OrderKey {
+    // A unique identifier for the device or client that authored the comment
+    // (e.g., a GUID). This serves as the main tie-breaker for comments with
+    // identical timestamps.
+    optional string device_guid = 1;
+
+    // A strictly monotonically increasing sequence number generated by the
+    // source device. Any sequence number is guaranteed to not be reused for the
+    // same source device.  This provides a final, definitive ordering for
+    // comments created by the same source, even if they arrive out of order.
+    optional int64 local_sequence = 2;
+  }
+  // A key for deterministically sorting entities.
+  optional OrderKey order_key = 3;
+}
+
+// Represents a single entity in the commenting system, which can be either a
+// user comment or a URL context object. This is the top-level message for a
+// single comment-related sync entity.
+message SharedCommentSpecifics {
+  // A unique identifier (UUID) for this entity.
+  optional string uuid = 1;
+
+  // A stable, permanent identifier for the collaboration context this entity
+  // belongs to. It serves as a permanent foreign key to group related data
+  // types (e.g., comments, tab groups) that belong to the same logical
+  // collaboration. This ID never changes, even if the underlying entity is
+  // shared or unshared, thus preventing data from being orphaned.
+  optional string context_id = 2;
+
+  // The highest SharedCommentSpecifics version supported by the client that
+  // wrote this entity.
+  optional int64 proto_version = 3;
+
+  // The main payload of this entity.
+  oneof entity {
+    // The content of a user-authored comment.
+    CommentData comment = 4;
+    // The context for a URL being commented on.
+    SharedUrlContext shared_url_context = 5;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/shared_tab_group_account_data_specifics.proto b/pyhindsight/lib/components/sync/protocol/shared_tab_group_account_data_specifics.proto
new file mode 100644
index 0000000..ce0dcba
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/shared_tab_group_account_data_specifics.proto
@@ -0,0 +1,61 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Account-local metadata for shared tab groups.
+// LINT.IfChange(SharedTabGroupAccountDataSpecifics)
+message SharedTabGroupAccountDataSpecifics {
+  // The guid of this entity.
+  // This could be the SharedTab guid (see SharedTabGroupDataSpecifics)
+  // or the SharedTabGroup guid.
+  optional string guid = 1;
+
+  // The collaboration group.
+  optional string collaboration_id = 2;
+
+  // Entities that contains information for a tab or a tab group.
+  oneof entity {
+    SharedTabDetails shared_tab_details = 3;
+    SharedTabGroupDetails shared_tab_group_details = 4;
+  }
+
+  // Timestamp when the message is updated.
+  optional int64 update_time_windows_epoch_micros = 5;
+
+  // A mechanism to identify the client version that wrote this specifics.
+  // Designed to aid business logic when reading newly added fields that
+  // didn't exist in older clients.
+  // The client version must be incremented whenever a new field is added to the
+  // specifics.
+  optional int32 version = 6;
+}
+
+// Stores account-specific metadata about a shared tab.
+message SharedTabDetails {
+  // The GUID of the SharedTabGroup this is a member of. This is the same
+  // as that from SharedTab in SharedTabGroupDataSpecifics.
+  optional string shared_tab_group_guid = 1;
+
+  // Last time this tab was focused.
+  optional int64 last_seen_timestamp_windows_epoch = 2;
+}
+
+message SharedTabGroupDetails {
+  // Position of the pinned tab group in bookmark bar on Desktop.
+  // This is equivalent to and compared against the pinned_position
+  // of message SavedTabGroup in saved_tab_group_specifics.proto.
+  optional int64 pinned_position = 1;
+}
+// LINT.ThenChange(//components/saved_tab_groups/internal/shared_tab_group_account_data_sync_bridge.cc:TrimSpecifics)
diff --git a/pyhindsight/lib/components/sync/protocol/shared_tab_group_data_specifics.proto b/pyhindsight/lib/components/sync/protocol/shared_tab_group_data_specifics.proto
new file mode 100644
index 0000000..22012ba
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/shared_tab_group_data_specifics.proto
@@ -0,0 +1,118 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for shared tab groups and tabs.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// copybara:uncomment_begin(google-only)
+// import "components/sync/protocol/sync_collaboration_attribution.proto";
+// copybara:uncomment_end
+
+import "components/sync/protocol/unique_position.proto";
+
+// LINT.IfChange(SharedTabGroupDataSpecifics)
+// IMPORTANT: please update
+// shared_tab_group_data_specifics_full_proto_unittest.cc if you change any
+// sync_collaboration_attribution FieldOptions.
+message SharedTabGroupDataSpecifics {
+  // Unique identifier for this entity.
+  optional string guid = 1;
+
+  oneof entity {
+    SharedTabGroup tab_group = 3;
+    SharedTab tab = 4;
+  }
+
+  optional int64 update_time_windows_epoch_micros = 5;
+
+  // A mechanism to identify the client version that wrote this specifics.
+  // Designed to aid business logic when reading newly added fields that
+  // didn't exist in older clients.
+  // The client version must be incremented whenever a new field is added to the
+  // specifics.
+  optional int32 version = 6;
+
+  reserved 2;
+}
+
+message SharedTabGroup {
+  // The displayed title of the group, shown on the tab group.
+  optional string title = 1
+      // copybara:uncomment_begin(google-only)
+      // [(sync_collaboration_attribution) = {
+      //   attribution_type: LAST_MODIFIED_BY_USER
+      //   name: "tab_group_title"
+      // }]
+      // copybara:uncomment_end
+      ;
+
+  // These colors map to tab_groups::TabGroupColorId. They DO NOT match the enum
+  // integer values due to "kGrey" being in the "Unspecified" field.
+  enum Color {
+    UNSPECIFIED = 0;
+    GREY = 1;
+    BLUE = 2;
+    RED = 3;
+    YELLOW = 4;
+    GREEN = 5;
+    PINK = 6;
+    PURPLE = 7;
+    CYAN = 8;
+    ORANGE = 9;
+  }
+  // The color of the tab group, mapped to tab_groups::TabGroupColorId.
+  optional Color color = 2
+      // copybara:uncomment_begin(google-only)
+      // [(sync_collaboration_attribution) = {
+      //   attribution_type: LAST_MODIFIED_BY_USER
+      //   name: "tab_group_color"
+      // }]
+      // copybara:uncomment_end
+      ;
+
+  // Saved tab group GUID from which this shared tab group was created.
+  optional string originating_tab_group_guid = 3;
+}
+
+message SharedTab {
+  // The URL of the page.
+  optional string url = 1
+      // copybara:uncomment_begin(google-only)
+      // [(sync_collaboration_attribution) = {
+      //   attribution_type: LAST_MODIFIED_BY_USER
+      //   name: "tab_url"
+      // }]
+      // copybara:uncomment_end
+      ;
+
+  // The title of the page.
+  optional string title = 2
+      // copybara:uncomment_begin(google-only)
+      // [(sync_collaboration_attribution) = {
+      //   attribution_type: LAST_MODIFIED_BY_USER
+      //   name: "tab_title"
+      // }]
+      // copybara:uncomment_end
+      ;
+
+  // The GUID of the SharedTabGroup this is a member of.
+  optional string shared_tab_group_guid = 4;
+  // The UniquePosition within a SharedTabGroup.
+  optional UniquePosition unique_position = 5;
+
+  reserved 3;
+  reserved "favicon_url";
+}
+// LINT.ThenChange(//components/saved_tab_groups/internal/shared_tab_group_data_sync_bridge.cc:TrimAllSupportedFieldsFromRemoteSpecifics)
diff --git a/pyhindsight/lib/components/sync/protocol/shared_tab_group_data_specifics_full_proto_unittest.cc b/pyhindsight/lib/components/sync/protocol/shared_tab_group_data_specifics_full_proto_unittest.cc
new file mode 100644
index 0000000..00144cf
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/shared_tab_group_data_specifics_full_proto_unittest.cc
@@ -0,0 +1,93 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/sync/protocol/shared_tab_group_data_specifics_full_proto.pb.h"
+#include "components/sync/protocol/sync_collaboration_attribution_full_proto.pb.h"
+#include "google/protobuf/descriptor.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using sync_pb::SharedTab;
+using sync_pb::SharedTabGroup;
+using sync_pb::SharedTabGroupDataSpecifics;
+using sync_pb::sync_collaboration_attribution;
+using sync_pb::SyncCollaborationAttribution;
+
+namespace {
+// Test annotations in uncommented full proto buffer.
+TEST(SharedTabGroupDataSpecificsFullProtoTest,
+     ShouldReflectAndReadCustomAnnotations) {
+  const google::protobuf::Descriptor* group_descriptor =
+      SharedTabGroup::descriptor();
+  ASSERT_TRUE(group_descriptor);
+
+  // Verify the 'title' field annotation.
+  const google::protobuf::FieldDescriptor* group_title_field =
+      group_descriptor->FindFieldByName("title");
+  ASSERT_TRUE(group_title_field);
+
+  const google::protobuf::FieldOptions& group_title_options =
+      group_title_field->options();
+  EXPECT_TRUE(group_title_options.HasExtension(sync_collaboration_attribution));
+
+  const SyncCollaborationAttribution& group_title_annotation =
+      group_title_options.GetExtension(sync_collaboration_attribution);
+
+  EXPECT_EQ(group_title_annotation.attribution_type(),
+            SyncCollaborationAttribution::LAST_MODIFIED_BY_USER);
+  EXPECT_EQ(group_title_annotation.name(), "tab_group_title");
+
+  // Verify the 'color' field annotation.
+  const google::protobuf::FieldDescriptor* group_color_field =
+      group_descriptor->FindFieldByName("color");
+  ASSERT_TRUE(group_color_field);
+
+  const google::protobuf::FieldOptions& group_color_options =
+      group_color_field->options();
+  EXPECT_TRUE(group_color_options.HasExtension(sync_collaboration_attribution));
+
+  const SyncCollaborationAttribution& group_color_annotation =
+      group_color_options.GetExtension(sync_collaboration_attribution);
+
+  EXPECT_EQ(group_color_annotation.attribution_type(),
+            SyncCollaborationAttribution::LAST_MODIFIED_BY_USER);
+  EXPECT_EQ(group_color_annotation.name(), "tab_group_color");
+
+  // Test annotations on SharedTab message
+  const google::protobuf::Descriptor* tab_descriptor = SharedTab::descriptor();
+  ASSERT_TRUE(tab_descriptor);
+
+  // Verify the 'url' field annotation.
+  const google::protobuf::FieldDescriptor* tab_url_field =
+      tab_descriptor->FindFieldByName("url");
+  ASSERT_TRUE(tab_url_field);
+
+  const google::protobuf::FieldOptions& tab_url_options =
+      tab_url_field->options();
+  EXPECT_TRUE(tab_url_options.HasExtension(sync_collaboration_attribution));
+
+  const SyncCollaborationAttribution& tab_url_annotation =
+      tab_url_options.GetExtension(sync_collaboration_attribution);
+
+  EXPECT_EQ(tab_url_annotation.attribution_type(),
+            SyncCollaborationAttribution::LAST_MODIFIED_BY_USER);
+  EXPECT_EQ(tab_url_annotation.name(), "tab_url");
+
+  // Verify the 'title' field annotation for tab.
+  const google::protobuf::FieldDescriptor* tab_title_field =
+      tab_descriptor->FindFieldByName("title");
+  ASSERT_TRUE(tab_title_field);
+
+  const google::protobuf::FieldOptions& tab_title_options =
+      tab_title_field->options();
+  EXPECT_TRUE(tab_title_options.HasExtension(sync_collaboration_attribution));
+
+  const SyncCollaborationAttribution& tab_title_annotation =
+      tab_title_options.GetExtension(sync_collaboration_attribution);
+
+  EXPECT_EQ(tab_title_annotation.attribution_type(),
+            SyncCollaborationAttribution::LAST_MODIFIED_BY_USER);
+  EXPECT_EQ(tab_title_annotation.name(), "tab_title");
+}
+
+}  // namespace
diff --git a/pyhindsight/lib/components/sync/protocol/sharing_message_specifics.proto b/pyhindsight/lib/components/sync/protocol/sharing_message_specifics.proto
new file mode 100644
index 0000000..37e8189
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/sharing_message_specifics.proto
@@ -0,0 +1,122 @@
+// Copyright 2020 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for sharing message.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+import "components/sync/protocol/unencrypted_sharing_message.proto";
+
+package sync_pb;
+
+message SharingMessageSpecifics {
+  // Unique identifier of message.
+  optional string message_id = 1;
+
+  message ChannelConfiguration {
+    message FCMChannelConfiguration {
+      // FCM registration token of target device.
+      optional string token = 1;
+
+      // Time to live for a FCM message (in seconds) - if specified, the message
+      // will expire based on the TTL.
+      optional int32 ttl = 2;
+
+      // Priority level of a FCM message. 5 = normal, 10 = high.
+      optional int32 priority = 3;
+    }
+
+    message ChimeChannelConfiguration {
+      // The channels supported for delivery in the notifications pipeline.
+      // Numbering should be kept in sync with
+      // google3/notifications/backend/proto/common/channel_types.proto.
+      enum ChimeChannelType {
+        CHANNEL_TYPE_UNSPECIFIED = 0;
+        // This uses the AppleSelection for selecting targets.
+        APPLE_PUSH = 2;
+      }
+      // The device registration token. For iOS, this should be the
+      // Apple device token.
+      optional bytes device_token = 1;
+
+      // Channel for delivery.
+      optional ChimeChannelType channel_type = 2;
+
+      // Identifies the type of this notification within Chime.
+      // The value of this field must correspond to a previously
+      // configured type for the "chrome_chime" client id at
+      // google3/googledata/notifications/config/clients/chrome_chime.
+      optional string type_id = 3;
+
+      // RTID provided by Chime after user is registered. Required if message
+      // should target specific device, otherwise optional.
+      optional string representative_target_id = 4;
+    }
+
+    oneof channel_configuration {
+      // FCM channel configuration. Message will be delivered as a FCM message.
+      FCMChannelConfiguration fcm = 1;
+
+      // Opaque server channel configuration. Message will be delivered through
+      // server channel.
+      bytes server = 2;
+
+      // Chime channel configuration. Message will be delivered through Chime.
+      ChimeChannelConfiguration chime = 3;
+    }
+  }
+
+  optional ChannelConfiguration channel_configuration = 2;
+
+  // Payload encrypted using the target user keys according to WebPush
+  // encryption scheme. The payload has to be a valid
+  // components/sharing_message/proto/sharing_message.proto serialized using
+  // SerializeToString.
+  optional bytes payload = 3;
+
+  // Payload NOT encrypted. For encrypted payloads, use payload field.
+  optional UnencryptedSharingMessage unencrypted_payload = 4;
+}
+
+// Used for the server to return fine grained commit errors back to the client.
+message SharingMessageCommitError {
+  // This enum is used in histograms. Entries should not be renumbered and
+  // numeric values should never be reused. Also remember to update in
+  // tools/metrics/histograms/enums.xml SyncSharingMessageCommitErrorCode enum.
+  // LINT.IfChange(SyncSharingMessageCommitErrorCode)
+  enum ErrorCode {
+    NONE = 0;
+    INVALID_ARGUMENT = 1;
+    NOT_FOUND = 2;
+    INTERNAL = 3;
+    UNAVAILABLE = 4;
+    RESOURCE_EXHAUSTED = 5;
+    UNAUTHENTICATED = 6;
+    PERMISSION_DENIED = 7;
+
+    // Client-specific error codes.
+    SYNC_TURNED_OFF = 8;
+    SYNC_NETWORK_ERROR = 9;
+    // Deprecated UMA bucket, prior to splitting between SYNC_SERVER_ERROR and
+    // SYNC_AUTH_ERROR.
+    DEPRECATED_SYNC_SERVER_OR_AUTH_ERROR = 10;
+    // Message wasn't committed before timeout.
+    SYNC_TIMEOUT = 11;
+    // Error code for server error or unparsable server response.
+    SYNC_SERVER_ERROR = 12;
+    // Auth error when communicating with the server.
+    SYNC_AUTH_ERROR = 13;
+  }
+  // LINT.ThenChange(/tools/metrics/histograms/metadata/sync/enums.xml:SyncSharingMessageCommitErrorCode)
+
+  optional ErrorCode error_code = 1;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/sync.proto b/pyhindsight/lib/components/sync/protocol/sync.proto
new file mode 100644
index 0000000..f3f519f
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/sync.proto
@@ -0,0 +1,512 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol for communication between sync client and server.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}. If you add new Specifics proto,
+// also update proto_value_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/client_commands.proto";
+import "components/sync/protocol/client_debug_info.proto";
+import "components/sync/protocol/data_type_progress_marker.proto";
+import "components/sync/protocol/get_updates_caller_info.proto";
+import "components/sync/protocol/password_sharing_invitation_specifics.proto";
+import "components/sync/protocol/sync_entity.proto";
+import "components/sync/protocol/sync_enums.proto";
+import "components/sync/protocol/sharing_message_specifics.proto";
+
+// This message contains diagnostic information used to correlate
+// commit-related traffic with extensions-related mutations to the
+// data models in chromium.  It plays no functional role in
+// processing this CommitMessage.
+message ChromiumExtensionsActivity {
+  // The human-readable ID identifying the extension responsible
+  // for the traffic reported in this ChromiumExtensionsActivity.
+  optional string extension_id = 1;
+
+  // How many times the extension successfully invoked a write
+  // operation through the bookmarks API since the last CommitMessage.
+  optional uint32 bookmark_writes_since_last_commit = 2;
+}
+
+// Client specific configuration information.
+message ClientConfigParams {
+  // The set of data types this client has enabled. Note that this does not
+  // include proxy types, as they do not have protocol field numbers and are
+  // placeholder types that implicitly enable protocol types.
+  repeated int32 enabled_type_ids = 1;
+
+  // Whether the PROXY_TABS proxy datatype is enabled on this client.
+  // Deprecated and not populated anymore since M120.
+  optional bool tabs_datatype_enabled = 2 [deprecated = true];
+
+  // Whether the account(s) present in the content area's cookie jar match the
+  // chrome account. If multiple accounts are present in the cookie jar, a
+  // mismatch implies all of them are different from the chrome account.
+  optional bool cookie_jar_mismatch = 3;
+
+  // Indicates that the client is not aware of any other active clients
+  // interested in the committed data types. This flag shows that it is not
+  // necessary to send invalidations for the committed data. A client is
+  // considered active if it's DeviceInfo has updated recent enough. This flag
+  // does not take into account whether standalone invalidations are enabled (as
+  // opposed to `single_client_with_standalone_invalidations`). However, it's
+  // set depending on interested data types of other devices, e.g. if there are
+  // other devices but they are not interested in SESSION data type, and current
+  // commit request contains only SESSION, it will be set to true.
+  // Introduced in M88.
+  optional bool single_client = 4;
+
+  // A list of FCM registration tokens which are obtained from other clients.
+  // This list is used by the server to send invalidations to all other clients.
+  // If the list is empty, the server should treat this as "there is no
+  // information about other clients". In practice, this happens by the next
+  // causes:
+  // 1. This is the old client which doesn't set this field.
+  // 2. There are too many active devices and the list would have too many
+  // items.
+  // 3. An empty list could also mean that the current client is the only
+  // client. This case should be covered by the
+  // `single_client_with_standalone_invalidations` field instead (otherwise it
+  // could be mixed up with older clients). The server doesn't have to use this
+  // field and can ignore it. Note that this list does not take into account
+  // interested data types from the other clients.
+  // Introduced in M89.
+  repeated string devices_fcm_registration_tokens = 5;
+
+  // Similar to `single_client` but takes into account only clients with enabled
+  // sync standalone invalidations. When set to true, there are no other clients
+  // with sync standalone invalidations interested in the committing types and
+  // hence it's not necessary to send out standalone invalidations (it may still
+  // be necessary to send out invalidations using the legacy system, see
+  // `single_client` instead).
+  // Introduced in M105.
+  optional bool single_client_with_standalone_invalidations = 6;
+
+  // Similar to `devices_fcm_registration_tokens` but takes into account clients
+  // which are subscribed to the data types which are committed in current
+  // commit request.
+  // A list of FCM registration tokens which are obtained from other clients.
+  // This list is used by the server to send invalidations to all other clients.
+  // If the list is empty, the server should treat this as "there is no
+  // information about other clients". In practice, this happens by the next
+  // causes:
+  // 1. This is the old client which doesn't set this field.
+  // 2. There are too many active devices and the list would have too many
+  // items.
+  // 3. An empty list could also mean that the current client is the only
+  // client. This case should be covered by the
+  // `single_client_with_standalone_invalidations` field instead (otherwise it
+  // could be mixed up with older clients). The server doesn't have to use this
+  // field and can ignore it.
+  // Introduced in M105.
+  repeated string fcm_registration_tokens_for_interested_clients = 7;
+
+  // Similar to `single_client` but takes into account only clients which are
+  // subscribed to old invalidations (i.e. not subscribed to sync standalone
+  // invalidations). When set to true, there are no other clients subscribed to
+  // old invalidations. Note that opposed to `single_client`, this flag does not
+  // always take into account the list of interested data types (because
+  // interested data types were introduced in M89). When the list is empty, a
+  // client is considered to be subscribed to all data types. Note that "single
+  // client" is a bit misleading since this will also be true if there are no
+  // clients with old invalidations at all.
+  // Introduced in M110.
+  optional bool single_client_with_old_invalidations = 8;
+}
+
+message CommitMessage {
+  repeated SyncEntity entries = 1;
+
+  // A GUID that identifies the committing sync client.  This value will be
+  // returned as originator_cache_guid for any new items.
+  optional string cache_guid = 2;
+
+  repeated ChromiumExtensionsActivity extensions_activity = 3;
+
+  // The configuration of this client at commit time. Used by the server to
+  // make commit-time decisions about how to process datatypes that might
+  // involve server-side interaction, and e.g require explicit user intent for
+  // syncing a particular data type regardless of whether a commit for that
+  // datatype is currently being sent up.
+  optional ClientConfigParams config_params = 4;
+
+  // Set of optional per-client datatype contexts.
+  repeated DataTypeContext client_contexts = 5;
+
+  // This field need to be 256 bytes if set. This attempts to mitigate CRIME
+  // attacks when sync communicate from client to server with compression. So if
+  // compression is used, this need to set a 256 random ASCII bytes. If no
+  // compression, this field should not be set. The server can ignore the
+  // padding.
+  optional string padding = 6;
+}
+
+message GetUpdatesMessage {
+  // Indicates the reason for the GetUpdatesMessage.
+  // This was *mostly* deprecated in M29.  GetUpdatesOrigin is the new way to
+  // encode the reason for the GetUpdates request, but some parts of the server
+  // still rely on this field.  It also still contains the
+  // "notifications_enabled" flag which needs to be moved elsewhere before this
+  // can be fully removed. See https://crbug.com/510165.
+  optional GetUpdatesCallerInfo caller_info = 2;
+
+  // Indicates whether related folders should be fetched.
+  optional bool fetch_folders = 3 [default = true];
+
+  // Per-datatype progress marker.
+  //
+  // With the exception of certain configuration or initial sync requests, the
+  // client should include one instance of this field for each enabled data
+  // type.
+  repeated DataTypeProgressMarker from_progress_marker = 6;
+
+  // Indicates whether the response should be sent in chunks.  This may be
+  // needed for devices with limited memory resources.  If true, the response
+  // will include one or more ClientToServerResponses, with the first one
+  // containing GetUpdatesMetadataResponse, and the remaining ones, if any,
+  // containing GetUpdatesStreamingResponse.  These ClientToServerResponses are
+  // delimited by a length prefix, which is encoded as a varint.
+  optional bool streaming = 7 [default = false];
+
+  // Whether the client needs the server to provide an encryption key for this
+  // account.
+  // Note: this should typically only be set on the first GetUpdates a client
+  // requests. Clients are expected to persist the encryption key from then on.
+  // The allowed frequency for requesting encryption keys is much lower than
+  // other datatypes, so repeated usage will likely result in throttling.
+  optional bool need_encryption_key = 8 [default = false];
+
+  // This value is an updated version of the GetUpdatesCallerInfo's
+  // GetUpdatesSource.  It describes the reason for the GetUpdate request.
+  // Introduced in M29.
+  optional SyncEnums.GetUpdatesOrigin get_updates_origin = 9;
+
+  // Whether this GU also serves as a retry GU. Any GU that happens after
+  // retry timer timeout is a retry GU effectively.
+  optional bool is_retry = 10 [default = false];
+
+  // Set of optional per-client datatype contexts.
+  repeated DataTypeContext client_contexts = 11;
+
+  reserved 1;
+  reserved "from_timestamp";
+  reserved 4;
+  reserved "requested_types";
+  reserved 5;
+  reserved "batch_size";
+  reserved 1000;
+  reserved "create_mobile_bookmarks_folder";
+}
+
+// Message from a client asking the server to clear its data. This causes the
+// server to generate a new store birthday, which allows dealing reliably with
+// in-flight requests (in particular commits) from other clients.
+message ClearServerDataMessage {
+  // No arguments needed as the store birthday and user identifier are part of
+  // an enclosing message.
+}
+
+// Response to a ClearServerData request.
+message ClearServerDataResponse {
+  // No result fields necessary. Success/failure is indicated in
+  // ClientToServerResponse.
+}
+
+// The client must preserve, store, and resend the chip bag with
+// every request.  The server depends on the chip bag in order
+// to precisely choreograph a client-server state machines.
+//
+// Because the client stores and sends this data on every request,
+// the contents of the chip bag should be kept relatively small.
+//
+// If the server does not return a chip bag, the client must assume
+// that there has been no change to the chip bag.  The client must
+// resend the bag of chips it had prior on the next request.
+//
+// The client must make the chip bag durable if and only if it
+// processes the response from the server.
+message ChipBag {
+  // Server chips are deliberately oqaque, allowing the server
+  // to encapsulate its state machine logic.
+  optional bytes server_chips = 1;
+}
+
+// Information about the syncer's state.
+message ClientStatus {
+  // Flag to indicate if the client has detected hierarchy conflcits.  The flag
+  // is left unset if update application has not been attempted yet.
+  //
+  // The server should attempt to resolve any hierarchy conflicts when this flag
+  // is set.  The client may not assume that any particular action will be
+  // taken.  There is no guarantee the problem will be addressed in a reasonable
+  // amount of time.
+  // TODO(crbug.com/40833583): Deprecated in M103.
+  optional bool hierarchy_conflict_detected = 1 [deprecated = true];
+
+  // Whether the client has full sync (or, sync the feature) enabled or not.
+  optional bool is_sync_feature_enabled = 2;
+}
+
+message ClientToServerMessage {
+  // `share` field is only used on the server for logging and can sometimes
+  // contain empty string. It is still useful for logging username when it can't
+  // be derived from access token in case of auth error.
+  required string share = 1;
+
+  optional int32 protocol_version = 2 [default = 99];
+  // LINT.IfChange(SyncClientToServerMessageContents)
+  enum Contents {
+    COMMIT = 1;
+    GET_UPDATES = 2;
+    DEPRECATED_3 = 3;
+    DEPRECATED_4 = 4;
+    CLEAR_SERVER_DATA = 5;
+  }
+  // LINT.ThenChange(/tools/metrics/histograms/metadata/sync/enums.xml:SyncClientToServerMessageContents)
+
+  // Each ClientToServerMessage contains one request defined by the
+  // message_contents. Each type has a corresponding message field that will be
+  // present iff the message is of that type. E.g. a commit message will have a
+  // message_contents of COMMIT and its commit field will be present.
+  required Contents message_contents = 3;
+  optional CommitMessage commit = 4;
+  optional GetUpdatesMessage get_updates = 5;
+  reserved 6;
+  reserved "authenticate";
+
+  // Opaque server-provided ID representing an "epoch" of the server-side data.
+  // Clients must hand this opaque ID back to the server as part of all requests
+  // within the same sync session (i.e. for all requests to the server except
+  // the very first GetUpdates request). See analogous field
+  // ClientToServerResponse.store_birthday for more details about its lifetime.
+  optional string store_birthday = 7;
+
+  reserved 8;
+  reserved "sync_problem_detected";
+  reserved 9;
+
+  // Client side state information for debugging purpose.
+  // This is only sent on the first getupdates of every sync cycle,
+  // as an optimization to save bandwidth.
+  optional DebugInfo debug_info = 10;
+
+  // Per-client state for use by the server. Sent with every message sent to the
+  // server.
+  optional ChipBag bag_of_chips = 11;
+
+  // Google API key.
+  optional string api_key = 12;
+
+  // Client's self-reported state.
+  // The client should set this on every message sent to the server, though its
+  // member fields may often be unset.
+  optional ClientStatus client_status = 13;
+
+  // The ID that our invalidation client used to identify itself to the server.
+  // Sending the ID here allows the server to not send notifications of our own
+  // changes to our invalidator.
+  // The field was deprecated in M117 and is no longer populated.
+  optional string invalidator_client_id = 14 [deprecated = true];
+
+  // Identifies this ClientToServerMessage as a clear server data request. This
+  // field is present when message_contents is CLEAR_SERVER_DATA.
+  optional ClearServerDataMessage clear_server_data = 15;
+}
+
+message CommitResponse {
+  enum ResponseType {
+    SUCCESS = 1;
+    CONFLICT = 2;  // You're out of date; update and check your data
+    // TODO(ncarter): What's the difference between RETRY and TRANSIENT_ERROR?
+    RETRY = 3;            // Someone has a conflicting, non-expired session open
+    INVALID_MESSAGE = 4;  // What the client sent was invalid, and trying again
+                          // won't help.
+    OVER_QUOTA = 5;  // This operation would put you, or you are, over quota
+    TRANSIENT_ERROR = 6;  // Something went wrong; try again in a bit
+  }
+  repeated group EntryResponse = 1 {
+    required ResponseType response_type = 2;
+
+    // Sync servers may also return a new ID for an existing item, indicating
+    // a new entry's been created to hold the data the client's sending up.
+    optional string id_string = 3;
+
+    reserved 4;
+    reserved "parent_id_string";
+
+    reserved 5;
+    reserved "position_in_parent";
+
+    // The version of this item -- a monotonically increasing value that is
+    // maintained by the server. See equivalent field in SyncEntity.
+    // If the returned version is smaller than the version the client already
+    // knew, the client will ignore the response, which means the item will
+    // still be considered to require a commit.
+    optional int64 version = 6;
+
+    reserved 7;
+    reserved "name";
+
+    reserved 8;
+    reserved "non_unique_name";
+
+    optional string error_message = 9;
+
+    // Last modification time (in milliseconds since Unix epoch).  Allows the
+    // server to override the client-supplied mtime during a commit operation.
+    // TODO(crbug.com/40751358): Delete this field too.
+    optional int64 mtime = 10 [deprecated = true];
+
+    message DatatypeSpecificError {
+      oneof datatype_error {
+        SharingMessageCommitError sharing_message_error = 1;
+        OutgoingPasswordSharingInvitationCommitError
+            outgoing_password_sharing_invitation_error = 2;
+      }
+    }
+    // Datatype specific error (if any).
+    optional DatatypeSpecificError datatype_specific_error = 11;
+  }
+}
+
+message GetUpdatesResponse {
+  // New sync entries that the client should apply.
+  repeated SyncEntity entries = 1;
+
+  reserved 2;
+  reserved "new_timestamp";
+
+  reserved 3;
+  reserved "newest_timestamp";
+
+  // Approximate count of changes remaining - use this for UI feedback.
+  // If present and zero, this estimate is firm: the server has no changes
+  // after the current batch.
+  optional int64 changes_remaining = 4;
+
+  // Opaque, per-datatype timestamp-like tokens.  Clients should retain and
+  // persist the values returned in this field, and present them back to the
+  // server to indicate the starting point for future update requests.
+  //
+  // This will be sent only if the client provided `from_progress_marker`
+  // in the update request.
+  //
+  // The server may provide a new progress marker even if this is the end of
+  // the batch, or if there were no new updates on the server; and the client
+  // must save these.  If the server does not provide a `new_progress_marker`
+  // value for a particular datatype, when the request provided a
+  // `from_progress_marker` value for that datatype, the client should
+  // interpret this to mean "no change from the previous state" and retain its
+  // previous progress-marker value for that datatype.
+  repeated DataTypeProgressMarker new_progress_marker = 5;
+
+  // The current encryption keys associated with this account. Will be set if
+  // the GetUpdatesMessage in the request had need_encryption_key == true or
+  // the server has updated the set of encryption keys (e.g. due to a key
+  // rotation).
+  repeated bytes encryption_keys = 6;
+
+  // Set of optional datatype contexts server mutations.
+  repeated DataTypeContext context_mutations = 7;
+}
+
+message ClientToServerResponse {
+  optional CommitResponse commit = 1;
+  optional GetUpdatesResponse get_updates = 2;
+  reserved 3;
+  reserved "authenticate";
+
+  // Up until protocol_version 24, the default was SUCCESS which made it
+  // impossible to add new enum values since older clients would parse any
+  // out-of-range value as SUCCESS. Starting with 25, unless explicitly set,
+  // the error_code will be UNKNOWN so that clients know when they're
+  // out-of-date. Note also that when using protocol_version < 25,
+  // TRANSIENT_ERROR is not supported. Instead, the server sends back a HTTP
+  // 400 error code. This is deprecated now.
+  optional SyncEnums.ErrorType error_code = 4 [default = UNKNOWN];
+  optional string error_message = 5;
+
+  // Opaque server-provided ID representing an "epoch" of the server-side data,
+  // referred to as "birthday" or "store birthday". This ID remains fixed until
+  // server-side data gets cleared/reset (e.g. via ClearServerDataMessage),
+  // which clients experience as NOT_MY_BIRTHDAY error, and involves clearing
+  // all local sync metadata including the cached store birthday.
+  //
+  // This mechanism allows the server to implement clear-data/reset
+  // functionality that reliably identifies and deletes sync entities uploaded
+  // before the clear-data/reset event (e.g. via ClearServerDataMessage).
+  // Furthermore, it allows the server to deal reliably with in-flight changes
+  // from other clients upon clear-data event, because all writes issued with an
+  // outdated birthday (which in-flight writes would use) can be detected by the
+  // server.
+  optional string store_birthday = 6;
+
+  optional ClientCommand client_command = 7;
+  reserved 8;
+  reserved "profiling_data";
+  reserved 9;
+  reserved 10;
+  reserved "stream_metadata";
+  reserved 11;
+  reserved "stream_data";
+
+  // The data types whose storage has been migrated.  Present when the value of
+  // error_code is MIGRATION_DONE.
+  repeated int32 migrated_data_type_id = 12;
+
+  message Error {
+    optional SyncEnums.ErrorType error_type = 1 [default = UNKNOWN];
+    optional string error_description = 2;
+    reserved 3;
+    reserved "url";
+    optional SyncEnums.Action action = 4 [default = UNKNOWN_ACTION];
+
+    // Currently meaningful if `error_type` is throttled or partial_failure.
+    // In the throttled case, if this field is absent then the whole client
+    // (all datatypes) is throttled.
+    // In the partial_failure case, this field denotes partial failures. The
+    // client should retry those datatypes with exponential backoff.
+    repeated int32 error_data_type_ids = 5;
+  }
+  optional Error error = 13;
+
+  // The new per-client state for this client. If set, should be persisted and
+  // sent with any subsequent ClientToServerMessages.
+  optional ChipBag new_bag_of_chips = 14;
+
+  // Present if this ClientToServerResponse is in response to a ClearServerData
+  // request.
+  optional ClearServerDataResponse clear_server_data = 15;
+}
+
+// A message to notify the server of certain sync events. Idempotent. Send these
+// to the /event endpoint. Note that this message is handled even when coming
+// from the legacy client (i.e. for which the server would reject
+// GetUpdates/Commit messages), that means breaking server-side changes need to
+// be handled carefully.
+message EventRequest {
+  optional SyncDisabledEvent sync_disabled = 1;
+}
+
+message EventResponse {}
+
+// A message indicating that the sync engine has been disabled on a client.
+message SyncDisabledEvent {
+  // The GUID that identifies the sync client.
+  optional string cache_guid = 1;
+
+  // The store birthday that the client was using before disabling sync.
+  optional string store_birthday = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/sync_collaboration_attribution.proto b/pyhindsight/lib/components/sync/protocol/sync_collaboration_attribution.proto
new file mode 100644
index 0000000..c8b25ea
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/sync_collaboration_attribution.proto
@@ -0,0 +1,54 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+package sync_pb;
+
+import "google/protobuf/descriptor.proto";
+
+// Configuration for per-field attribution in collaborative Sync data types.
+// Attaching this as an option to a field within a Sync entity's proto
+// definition (e.g., in a SharedTab or SharedTabGroup) enables the tracking of
+// metadata related to cross-user collaboration, such as which user last
+// modified that specific field.
+message SyncCollaborationAttribution {
+  enum AttributionType {
+    // Default value. No attribution tracking for this field.
+    NONE = 0;
+    // Track the user who last modified this field.
+    LAST_MODIFIED_BY_USER = 1;
+  }
+
+  // Specifies the type of attribution to be applied to the annotated field.
+  optional AttributionType attribution_type = 1;
+
+  // A stable identifier for the annotated field, used to distinguish it from
+  // other fields within the same Chrome Sync data type message that also
+  // have attribution annotations. This identifier is used to associate
+  // attribution information (like the last modifier) with this specific field
+  // of the Sync Entity.
+  //
+  // This name is also used in the metadata of SyncEntity that are sent to
+  // clients, such that the client code key to find the related attribution
+  // data.
+  //
+  // Because of this, the name MUST be unique across all fields annotated with
+  // `sync_collaboration_attribution` within a single EntitySpecifics. For
+  // example, all `name` values within `SharedTabGroupData` must be distinct.
+  //
+  // Recommended format: `lower_snake_case`.
+  // Examples: "tab_group_title", "tab_url", "tab_group_color".
+  optional string name = 2;
+}
+
+extend google.protobuf.FieldOptions {
+  // IMPORTANT: the extension number needs to be declared. See
+  // go/extension-declaration-reserved-numbers for more information.
+  optional SyncCollaborationAttribution sync_collaboration_attribution =
+      535801565;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/sync_entity.proto b/pyhindsight/lib/components/sync/protocol/sync_entity.proto
new file mode 100644
index 0000000..64e2c9e
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/sync_entity.proto
@@ -0,0 +1,281 @@
+// Copyright 2021 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/deletion_origin.proto";
+import "components/sync/protocol/entity_specifics.proto";
+import "components/sync/protocol/unique_position.proto";
+
+message SyncEntity {
+  // This item's identifier.  In a commit of a new item, this will be a
+  // client-generated ID.  If the commit succeeds, the server will generate
+  // a globally unique ID and return it to the committing client in the
+  // CommitResponse.EntryResponse.  In the context of a GetUpdatesResponse,
+  // `id_string` is always the server generated ID.  The original
+  // client-generated ID is preserved in the `originator_client_id` field.
+  // Present in both GetUpdatesResponse and CommitMessage.
+  // Prior to M123, this field was empty for commit-only types.
+  optional string id_string = 1;
+
+  // An id referencing this item's parent in the hierarchy.  In a
+  // CommitMessage, it is accepted for this to be a client-generated temporary
+  // ID if there was a new created item with that ID appearing earlier
+  // in the message.  In all other situations, it is a server ID.
+  // Present in both GetUpdatesResponse and CommitMessage.
+  //
+  // Starting with M99, this field is optional and used for legacy bookmarks
+  // only:
+  // 1. When processing GetUpdatesResponse, it is unused for modern data created
+  //    or reuploaded by M94 or above, which populates the parent's GUID in
+  //    BookmarkSpecifics (which is sufficient).
+  // 2. When issuing CommitMessage, the field is populated for compatibility
+  //    with clients before M99.
+  optional string parent_id_string = 2;
+
+  reserved 3;
+  reserved "old_parent_id";
+
+  // The version of this item -- a monotonically increasing value that is
+  // maintained by the server (or more precisely, the storage backend). It is
+  // typically a timestamp, in microseconds since the Unix epoch, of the last
+  // backend write. Present in both CommitMessage (set by the client) and
+  // GetUpdatesResponse (set by the server), and there's also an equivalent
+  // field in CommitResponse.
+  //
+  // In a CommitMessage, `version` is set to zero for newly-created items. For
+  // updates to existing items, it is set by the client to the last version the
+  // client knew about when sending the commit. If this version does not match
+  // the latest version on the server, the commit *may* fail for that item with
+  // a result code of CONFLICT. However, this is not guaranteed, and in
+  // practice is not implemented for most data types.
+  //
+  // In a GetUpdatesResponse, `version` is always positive and identifies the
+  // revision of the item stored in the server backend. If the returned version
+  // is smaller than the version the client already knew, the client will ignore
+  // the response.
+  //
+  // WARNING: This field used to be required before M60. Any client before this
+  // will fail to deserialize if this field is missing.
+  optional int64 version = 4;
+
+  // Last modification time, in milliseconds since Unix epoch.
+  // Present in both GetUpdatesResponse and CommitMessage.
+  optional int64 mtime = 5;
+
+  // Creation time, in milliseconds since Unix epoch.
+  // Present in both GetUpdatesResponse and CommitMessage.
+  optional int64 ctime = 6;
+
+  // The name of this item.
+  // Historical note:
+  //   Since November 2010, this value is no different from non_unique_name.
+  //   Before then, server implementations would maintain a unique-within-parent
+  //   value separate from its base, "non-unique" value.  Clients had not
+  //   depended on the uniqueness of the property since November 2009; it was
+  //   removed from Chromium by http://codereview.chromium.org/371029 .
+  // Present in both GetUpdatesResponse and CommitMessage.
+  // WARNING: This field used to be required before M60. Any client before this
+  // will fail to deserialize if this field is missing.
+  optional string name = 7;
+
+  // The name of this item.  Same as `name`.
+  // `non_unique_name` should take precedence over the `name` value if both
+  // are supplied.  For efficiency, clients and servers should avoid setting
+  // this redundant value.
+  // Present in both GetUpdatesResponse and CommitMessage.
+  optional string non_unique_name = 8;
+
+  reserved 9;
+  reserved "sync_timestamp";
+
+  // If present, this tag identifies this item as being a uniquely
+  // instanced item.  The server ensures that there is never more
+  // than one entity in a user's store with the same tag value.
+  // This value is used to identify and find e.g. the "Bookmark Bar" folder
+  // without relying on a particular ID or name.
+  //
+  // This variant of the tag is created by the server, so clients can't create
+  // an item with a tag using this field.
+  //
+  // Use client_tag_hash if you want to create one from the client.
+  //
+  // An item can't have both a client_tag_hash and
+  // a server_defined_unique_tag.
+  //
+  // Present only in GetUpdatesResponse.
+  optional string server_defined_unique_tag = 10;
+
+  reserved 11;
+  reserved "BookmarkData";
+  reserved 12;
+  reserved "bookmark_folder";
+  reserved 13;
+  reserved "bookmark_url";
+  reserved 14;
+  reserved "bookmark_favicon";
+
+  // Ancient fields, predecessors for `unique_position`, deprecated with M26 and
+  // still supported to deal with old incoming data. See field `unique_position`
+  // for details as well as the data-upgrading implementation in
+  // GetUniquePositionFromSyncEntity().
+  optional int64 position_in_parent = 15 [deprecated = true];
+  optional string insert_after_item_id = 16 [deprecated = true];
+
+  reserved 17;
+  reserved "extended_attributes";
+
+  // If true, indicates that this item has been (or should be) deleted.
+  // Present in both GetUpdatesResponse and CommitMessage.
+  optional bool deleted = 18 [default = false];
+
+  // A unique ID that identifies the the sync client who initially committed
+  // this entity.  This value corresponds to `cache_guid` in CommitMessage.
+  // This field, along with `originator_client_item_id`, can be used to
+  // reunite the original with its official committed version in the case
+  // where a client does not receive or process the commit response for
+  // some reason.
+  //
+  // Present only in GetUpdatesResponse.
+  //
+  // This field is also used in determining the unique identifier used in
+  // bookmarks' unique_position field.
+  optional string originator_cache_guid = 19;
+
+  // Item ID as generated by the client that initially created this entity. Used
+  // exclusively for bookmarks (other datatypes use client_tag_hash).
+  // There are three generation of bookmarks that have populated this field
+  // differently, depending on which version of the browser created the
+  // bookmark:
+  // 1. For bookmarks created before M44 (2015), the field got populated with an
+  //    ID that is locally unique, but not globally unique (usually a negative
+  //    number).
+  // 2. For bookmarks created between M45 and M51, both inclusive, the field got
+  //    populated with a globally unique GUID in uppercase form.
+  // 3. For bookmarks created with M52 or above, the field gets populated with
+  //    a globally unique GUID in lowercase form.
+  //
+  // Present only in GetUpdatesResponse.
+  optional string originator_client_item_id = 20;
+
+  // Extensible container for datatype-specific data.
+  // This became available in version 23 of the protocol.
+  optional EntitySpecifics specifics = 21;
+
+  // Indicate whether this is a folder or not. Available in version 23+.
+  optional bool folder = 22 [default = false];
+
+  // A client defined unique hash for this entity.
+  // Analogous to server_defined_unique_tag, but allows the client to determine
+  // an immutable attribute of the entity in hashed form that makes it unique
+  // per user (i.e. at most one entity may exist per client tag hash).
+  //
+  // This value must be of the form base64(SHA1(client_tag)) where the
+  // client_tag is a value derived from the contents of an entity in a
+  // type-specific way. Since the hashed contents of the client_tag are exposed
+  // to the server via this field, take care when defining it that there is
+  // enough entropy to mask any secrets that the server shouldn't learn.
+  //
+  // The difference between server_defined_unique_tag and
+  // client_tag_hash is the creator of the entity. Server defined
+  // tags are entities created by the server at account creation,
+  // while client defined tags are entities created by the client at any time.
+  //
+  // During GetUpdates, a sync entity update will come back with ONE of:
+  // a) Originator item and cache id - for bookmarks created using old versions
+  //    of the browser (latest M93, before https://crrev.com/c/2945119).
+  // b) Server tag - If server committed the item as unique
+  // c) Client tag - If client committed the item as unique
+  //
+  // May be present in CommitMessages for the initial creation of an entity.
+  // If present in Commit updates for the entity, it will be ignored.
+  //
+  // May be returned in GetUpdatesMessage and sent up in CommitMessage.
+  optional string client_tag_hash = 23;
+
+  // Field 23 was previously named client_defined_unique_tag, avoid reuse.
+  reserved "client_defined_unique_tag";
+
+  reserved 24;
+  reserved "ordinal_in_parent";
+
+  // Introduced in M26, represents ordering among entities, in practice used for
+  // bookmarks only. Clients should not assume it is always populated in
+  // GetUpdatesMessage due to the following caveats:
+  // 1. Tombstones and permanent folders do not populate it (ordering is
+  //    irrelevant).
+  // 2. It may remain unset by future versions of the client, as long as the
+  //    field with the same name is populated inside BookmarkSpecifics. M94 and
+  //    above populate both for backward compatibility reasons, but when support
+  //    for M93 is retired, modern clients at the time may stop populating this
+  //    field.
+  // 3. Very old data (last committed by M25 or below, before the field was
+  //    introduced) does not include this field, and in that case the legacy
+  //    fields `position_in_parent` or `insert_after_item_id` must be honored
+  //    instead.
+  //
+  // May be returned in GetUpdatesMessage and sent up in CommitMessage.
+  optional UniquePosition unique_position = 25;
+
+  // This used to be a list of sync attachment IDs, but it was never launched
+  // and the code has been removed as of M66.
+  reserved 26;
+  reserved "attachment_id";
+
+  // Metadata used for shared data types. Must not be present for regular data
+  // types.
+  // Introduced in M124.
+  message CollaborationMetadata {
+    // Attribution metadata for this whole SyncEntity.
+    message Attribution {
+      // Obfuscated Gaia ID of the user.
+      optional string obfuscated_gaia_id = 1;
+    }
+
+    // Per field attribution metadata (e.g, tab_group_color, tab_group_name.)
+    // Introduced in M141.
+    message PerFieldAttribution {
+      // Name of the attribution that uniquely identifies the changed field
+      // (e.g. tab_group_title). These should have the same values as those
+      // provided through the proto FieldOptions. See
+      // `SharedTabGroupDataSpecifics` for examples.
+      optional string attribution_name = 1;
+
+      // Obfuscated Gaia ID of the user that last modified this.
+      optional string last_update_obfuscated_gaia_id = 2;
+
+      // Last modification time of the specific attribution, in milliseconds
+      // since Unix epoch.
+      optional int64 mtime = 3;
+    }
+
+    // Collaboration ID which the current entity belongs to.
+    optional string collaboration_id = 1;
+
+    // Information about when the specifics was created.
+    optional Attribution creation_attribution = 2;
+
+    // Information about when the specifics was last updated.
+    optional Attribution last_update_attribution = 3;
+
+    repeated PerFieldAttribution per_field_attributions = 4;
+  }
+
+  optional CollaborationMetadata collaboration = 27;
+
+  // Optionally present in CommitMessage for committed deletions (but may remain
+  // unset if the origin is unspecified), it represents which piece of code
+  // triggered a deletion. It is a debug-only field with no compatibility
+  // guarantees, subject to change over time. The main purpose is to help with
+  // investigating and mitigating user reports or incidents that cause data
+  // deletion. Introduced in M126.
+  optional DeletionOrigin deletion_origin = 28;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/sync_enums.proto b/pyhindsight/lib/components/sync/protocol/sync_enums.proto
new file mode 100644
index 0000000..746dcf9
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/sync_enums.proto
@@ -0,0 +1,242 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol for communication between sync client and server.
+
+// If you change or add any enums in this file, update
+// proto_enum_conversions.{h, cc}.
+// If you deprecate enum or enum values, mark any corresponding entry in
+// tools/metrics/histograms/enums.xml as <obsolete>.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message SyncEnums {
+  // These events are sent by the DebugInfo class for singleton events.
+  enum SingletonDebugEventType {
+    // Connection status change. Note this gets generated even during a
+    // successful connection.
+    CONNECTION_STATUS_CHANGE = 1;
+    // Client received an updated token.
+    UPDATED_TOKEN = 2;
+    // Cryptographer needs passphrase.
+    PASSPHRASE_REQUIRED = 3;
+    // Passphrase was accepted by cryptographer.
+    PASSPHRASE_ACCEPTED = 4;
+    // Sync Initialization is complete.
+    INITIALIZATION_COMPLETE = 5;
+    // Server sent stop syncing permanently. This event should never be seen by
+    // the server in the absence of bugs.
+    STOP_SYNCING_PERMANENTLY = 6;
+    // Client has finished encrypting all data.
+    // DEPRECATED_ENCRYPTION_COMPLETE = 7;
+    // Client received an actionable error.
+    ACTIONABLE_ERROR = 8;
+    // Set of encrypted types has changed.
+    ENCRYPTED_TYPES_CHANGED = 9;
+    // The encryption passphrase state changed.
+    PASSPHRASE_TYPE_CHANGED = 10;
+    // A new keystore encryption token was persisted. Deprecated 11/2021.
+    DEPRECATED_KEYSTORE_TOKEN_UPDATED = 11;
+    // The datatype manager has finished an at least partially successful
+    // configuration and is once again syncing with the server.
+    CONFIGURE_COMPLETE = 12;
+    // A new cryptographer bootstrap token was generated.
+    DEPRECATED_BOOTSTRAP_TOKEN_UPDATED = 13;
+    // Cryptographer needs trusted vault decryption keys.
+    TRUSTED_VAULT_KEY_REQUIRED = 14;
+    // Cryptographer no longer needs trusted vault decryption keys.
+    TRUSTED_VAULT_KEY_ACCEPTED = 15;
+  }
+
+  // See ui/base/page_transition_types.h for detailed information on the
+  // values of PageTransition and PageTransitionRedirectType below.
+
+  // Types of transitions between pages.
+  enum PageTransition {
+    LINK = 0;
+    TYPED = 1;
+    AUTO_BOOKMARK = 2;
+    AUTO_SUBFRAME = 3;
+    MANUAL_SUBFRAME = 4;
+    GENERATED = 5;
+    AUTO_TOPLEVEL = 6;
+    FORM_SUBMIT = 7;
+    RELOAD = 8;
+    KEYWORD = 9;
+    KEYWORD_GENERATED = 10;
+    // The below two were mistakenly added but never properly used. They are
+    // actually transition qualifiers, and are set independently of other
+    // qualifiers and of the main transitions. See session_specifics.proto for
+    // the list of synced transition qualifiers.
+    // DEPRECATED_CHAIN_START = 12;
+    // DEPRECATED_CHAIN_END = 13;
+  }
+
+  // Types of redirects that triggered a transition.
+  enum PageTransitionRedirectType {
+    CLIENT_REDIRECT = 1;
+    SERVER_REDIRECT = 2;
+  }
+
+  enum ErrorType {
+    SUCCESS = 0;
+    // DEPRECATED_ACCESS_DENIED = 1;
+    // Returned when the server and client disagree on the store birthday. This
+    // should be interpreted as all local sync metadata requiring cleanup,
+    // obviously including the locally-cached store birthday.
+    NOT_MY_BIRTHDAY = 2;
+    // Returned when the store has exceeded the allowed bandwidth utilization.
+    THROTTLED = 3;
+    // DEPRECATED_AUTH_EXPIRED = 4;
+    // DEPRECATED_USER_NOT_ACTIVATED = 5;
+    // DEPRECATED_AUTH_INVALID = 6;
+    // DEPRECATED_CLEAR_PENDING = 7;
+    // A transient error occurred (e.g. a backend timeout). The client should
+    // try again later.
+    TRANSIENT_ERROR = 8;
+    // A server-side migration has taken place for one or more data types. The
+    // client should clear the cache for these data types only and then re-sync
+    // with a server.
+    MIGRATION_DONE = 9;
+    // An administrator disabled sync for this domain.
+    DISABLED_BY_ADMIN = 10;
+    // Deprecated in M50.
+    // DEPRECATED_USER_ROLLBACK = 11;
+    // Returned when the client wants to update several data types, but some of
+    // them failed (e.g. throttled).
+    PARTIAL_FAILURE = 12;
+    // Returned when the server detects that this client's sync metadata is
+    // obsolete. The client should reset local sync metadata and restart
+    // syncing.
+    CLIENT_DATA_OBSOLETE = 13;
+    // Returned when the server detects that the encryption state (Nigori,
+    // keystore keys) has been reset/overridden, which means the local
+    // Nigori-related state is obsolete and should be cleared.
+    // Introduced in M84.
+    ENCRYPTION_OBSOLETE = 14;
+    // Unknown value. This should never be explicitly used; it is the default
+    // value when an out-of-date client parses a value it doesn't recognize.
+    UNKNOWN = 100;
+  }
+
+  enum Action {
+    UPGRADE_CLIENT = 0;  // Upgrade the client to latest version.
+    // DEPRECATED_CLEAR_USER_DATA_AND_RESYNC = 1;
+    // DEPRECATED_ENABLE_SYNC_ON_ACCOUNT = 2;
+    // DEPRECATED_STOP_AND_RESTART_SYNC = 3;
+    // DEPRECATED_DISABLE_SYNC_ON_CLIENT = 4;
+    UNKNOWN_ACTION = 5;  // This is the default.
+  }
+
+  // New enums to describe the device type were introduced; OsType and
+  // FormFactor. Deprecated 12/2022.
+  // TODO(crbug.com/40882073): Remove deprecated values from DeviceType enum.
+  enum DeviceType {
+    TYPE_UNSET = 0 [deprecated = true];
+    TYPE_WIN = 1 [deprecated = true];
+    TYPE_MAC = 2 [deprecated = true];
+    TYPE_LINUX = 3 [deprecated = true];
+    TYPE_CROS = 4 [deprecated = true];
+    TYPE_OTHER = 5 [deprecated = true];
+    TYPE_PHONE = 6 [deprecated = true];
+    TYPE_TABLET = 7 [deprecated = true];
+  }
+
+  // Types of device OS.
+  enum OsType {
+    OS_TYPE_UNSPECIFIED = 0;
+    OS_TYPE_WINDOWS = 1;
+    OS_TYPE_MAC = 2;
+    OS_TYPE_LINUX = 3;
+    OS_TYPE_CHROME_OS_ASH = 4;
+    OS_TYPE_ANDROID = 5;
+    OS_TYPE_IOS = 6;
+    OS_TYPE_CHROME_OS_LACROS = 7;
+    OS_TYPE_FUCHSIA = 8;
+  }
+
+  // Types of device form factors.
+  enum DeviceFormFactor {
+    DEVICE_FORM_FACTOR_UNSPECIFIED = 0;
+    DEVICE_FORM_FACTOR_DESKTOP = 1;
+    DEVICE_FORM_FACTOR_PHONE = 2;
+    DEVICE_FORM_FACTOR_TABLET = 3;
+    DEVICE_FORM_FACTOR_AUTOMOTIVE = 4;
+    DEVICE_FORM_FACTOR_WEARABLE = 5;
+    DEVICE_FORM_FACTOR_TV = 6;
+  }
+
+  // Types of browsers; used for history-related data types.
+  enum BrowserType {
+    BROWSER_TYPE_UNKNOWN = 0;
+    TYPE_TABBED = 1;      // A normal tabbed window.
+    TYPE_POPUP = 2;       // A popup window.
+    TYPE_CUSTOM_TAB = 3;  // A custom tab within an app.
+    TYPE_AUTH_TAB = 4;    // A auth-dedicated custom tab within an app.
+  }
+
+  // The "password state" is the presence/absence of a password field on a
+  // website; used for history-related data types.
+  enum PasswordState {
+    PASSWORD_STATE_UNKNOWN = 0;
+    NO_PASSWORD_FIELD = 1;
+    HAS_PASSWORD_FIELD = 2;
+  }
+
+  // This is the successor to GetUpdatesSource.  It merges the "normal mode"
+  // values (LOCAL, NOTIFICATION and DATATYPE_REFRESH), which were never really
+  // mutually exclusive to being with, into the GU_TRIGGER value.  It also
+  // drops support for some old values that are not supported by newer clients.
+  //
+  // Mind the gaps: Some values are intentionally unused because we want to
+  // keep the values in sync with GetUpdatesSource as much as possible.  Please
+  // don't add any values < 12 unless there's a good reason for it.
+  //
+  // Introduced in M28.
+  // LINT.IfChange(SyncGetUpdatesOrigin)
+  enum GetUpdatesOrigin {
+    UNKNOWN_ORIGIN = 0;  // The source was not set by the caller.
+    PERIODIC = 4;        // The source of the update was periodic polling.
+    NEWLY_SUPPORTED_DATATYPE = 7;  // The client is in configuration mode
+                                   // because it's syncing all datatypes, and
+                                   // support for a new datatype was recently
+                                   // released via a software auto-update.
+    MIGRATION = 8;         // The client is in configuration mode because a
+                           // MIGRATION_DONE error previously returned by the
+                           // server necessitated resynchronization.
+    NEW_CLIENT = 9;        // The client is in configuration mode because the
+                           // user enabled sync for the first time.  Not to be
+                           // confused with FIRST_UPDATE.
+    RECONFIGURATION = 10;  // The client is in configuration mode because the
+                           // user opted to sync a different set of datatypes.
+    GU_TRIGGER = 12;  // The client is in 'normal' mode.  It may have several
+                      // reasons for requesting an update.  See the per-type
+                      // GetUpdateTriggers message for more details.
+    // DEPRECATED_RETRY = 13;
+    PROGRAMMATIC = 14;  // A GU to programmatically enable/disable a
+                        // datatype, often due to error handling.
+
+    reserved 13;
+    reserved "RETRY";
+  }
+  // LINT.ThenChange(/tools/metrics/histograms/metadata/sync/enums.xml:SyncGetUpdatesOrigin)
+
+  // Type of message sent to the receiving device for the send tab to self
+  // feature.
+  enum SendTabReceivingType {
+    // Send tab notification can be received as an in-app message. This is the
+    // default value.
+    SEND_TAB_RECEIVING_TYPE_CHROME_OR_UNSPECIFIED = 0;
+    // Send tab notification can be received as a push notification and/or
+    // in-app message.
+    SEND_TAB_RECEIVING_TYPE_CHROME_AND_PUSH_NOTIFICATION = 1;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/sync_invalidations_payload.proto b/pyhindsight/lib/components/sync/protocol/sync_invalidations_payload.proto
new file mode 100644
index 0000000..b108dd6
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/sync_invalidations_payload.proto
@@ -0,0 +1,37 @@
+// Copyright 2020 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// The payload coming from the server for all invalidated data types.
+message SyncInvalidationsPayload {
+  message DataTypeInvalidation {
+    // The legitimate values of this field correspond to the protobuf field
+    // numbers of all EntitySpecifics fields supported by the server (see
+    // components/sync/protocol/sync.proto).
+    optional int32 data_type_id = 1;
+  }
+
+  // This field contains information about each data type which needs to be
+  // updated. Note that it may contain data types which current client is not
+  // interested in.
+  repeated DataTypeInvalidation data_type_invalidations = 1;
+
+  // Opaque field, which has to be provided as part of resulting GetUpdates
+  // back to the server.
+  optional bytes hint = 2;
+
+  // Version of invalidation, used to order incoming invalidations.
+  optional int64 version = 3;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/tab_group_attribution_metadata.proto b/pyhindsight/lib/components/sync/protocol/tab_group_attribution_metadata.proto
new file mode 100644
index 0000000..73966b3
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/tab_group_attribution_metadata.proto
@@ -0,0 +1,42 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Stores information about the creation and modification of a tab group or tab.
+message AttributionMetadata {
+  // Details about a single attribution event (creation or modification).
+  message Attribution {
+    // Information about the device where the attribution event occurred.
+    message AttributionDeviceInfo {
+      // The unique identifier for the device in the sync system.
+      optional string cache_guid = 1;
+    }
+
+    // Information about the device.
+    optional AttributionDeviceInfo device_info = 1;
+  }
+
+  // Identifier for device that refers to the device that created the group.
+  // Should only be set on creation, and should not be edited if the value is
+  // missing.
+
+  // Information about when the specifics was created.
+  // The cache guid should only be set on creation and not be edited if the
+  // value is missing.
+  optional Attribution created = 1;
+
+  // Information about when the specifics was last updated.
+  optional Attribution updated = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/test.proto b/pyhindsight/lib/components/sync/protocol/test.proto
new file mode 100644
index 0000000..c416a51
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/test.proto
@@ -0,0 +1,23 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Protocol messages used only for testing.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message UnknownFieldsTestA {
+  required bool foo = 1;
+}
+
+message UnknownFieldsTestB {
+  required bool foo = 1;
+  required bool bar = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/theme_specifics.proto b/pyhindsight/lib/components/sync/protocol/theme_specifics.proto
new file mode 100644
index 0000000..ff4aa41
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/theme_specifics.proto
@@ -0,0 +1,67 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for themes.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/theme_types.proto";
+
+// Properties of theme sync objects.
+message ThemeSpecifics {
+  // Set iff a theme extension exists, in which case, all custom_ fields should
+  // be present. This is false for all other theme types (for example,
+  // autogenerated or user color theme). If not set, all custom_* fields
+  // should be omitted.
+  optional bool use_custom_theme = 1;
+
+  // This field is only relevant on platforms that have a distinction between
+  // the system theme and the default theme, but other platforms must be careful
+  // to pass through the value of this flag.
+  //
+  // If true, we use the system theme by default (i.e., when we don't use a
+  // custom theme) for platforms that make a distinction between the default
+  // theme and the system theme. Has no effect if use_custom_theme is true.
+  optional bool use_system_theme_by_default = 2;
+
+  // Extension specific fields. Ignored unless `use_custom_theme` is true.
+  optional string custom_theme_name = 3;
+  optional string custom_theme_id = 4;
+  optional string custom_theme_update_url = 5;
+
+  message AutogeneratedColorTheme {
+    // SkColor used to autogenerate theme.
+    optional uint32 color = 1;
+  }
+
+  message Empty {}
+
+  // The browser-built color theme can be either be autogenerated,
+  // user-selected, or grayscale.
+  oneof color {
+    AutogeneratedColorTheme autogenerated_color_theme = 6;
+    UserColorTheme user_color_theme = 7;
+    Empty grayscale_theme_enabled = 8;
+  }
+
+  enum BrowserColorScheme {
+    BROWSER_COLOR_SCHEME_UNSPECIFIED = 0;
+    SYSTEM = 1;
+    LIGHT = 2;
+    DARK = 3;
+  }
+  optional BrowserColorScheme browser_color_scheme = 9;
+
+  optional NtpCustomBackground ntp_background = 10;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/theme_specifics_ios.proto b/pyhindsight/lib/components/sync/protocol/theme_specifics_ios.proto
new file mode 100644
index 0000000..32f865b
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/theme_specifics_ios.proto
@@ -0,0 +1,26 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for themes on iOS.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/theme_types.proto";
+
+// Properties of theme sync objects for iOS themes.
+message ThemeSpecificsIos {
+  optional UserColorTheme user_color_theme = 1;
+
+  optional NtpCustomBackground ntp_background = 2;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/theme_types.proto b/pyhindsight/lib/components/sync/protocol/theme_types.proto
new file mode 100644
index 0000000..0141cd7
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/theme_types.proto
@@ -0,0 +1,50 @@
+// Copyright 2025 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Helper sync types for theme syncing.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message UserColorTheme {
+  enum BrowserColorVariant {
+    BROWSER_COLOR_VARIANT_UNSPECIFIED = 0;
+    SYSTEM = 1;
+    TONAL_SPOT = 2;
+    NEUTRAL = 3;
+    VIBRANT = 4;
+    EXPRESSIVE = 5;
+  }
+  optional uint32 color = 1;
+  optional BrowserColorVariant browser_color_variant = 2;
+}
+
+// Custom NTP background info.
+message NtpCustomBackground {
+  // Background image url.
+  optional string url = 1;
+  // Attribution strings for the image.
+  optional string attribution_line_1 = 2;
+  optional string attribution_line_2 = 3;
+  // Url to learn more info about the image.
+  optional string attribution_action_url = 4;
+  // Id of the collection being used.
+  optional string collection_id = 5;
+  // Token to get the next image from collection and avoid duplicates.
+  optional string resume_token = 6;
+  // Timestamp after which the next image should be fetched from the
+  // collection.
+  optional int64 refresh_timestamp_unix_epoch_seconds = 7;
+  // Main color of the image.
+  optional uint32 main_color = 8;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/typed_url_specifics.proto b/pyhindsight/lib/components/sync/protocol/typed_url_specifics.proto
new file mode 100644
index 0000000..537afbc
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/typed_url_specifics.proto
@@ -0,0 +1,40 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for typed urls.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Properties of typed_url sync objects - fields correspond to similarly named
+// fields in history::URLRow.
+message TypedUrlSpecifics {
+  // Actual URL that was typed.
+  optional string url = 1;
+  // Title of the page corresponding to this URL.
+  optional string title = 2;
+  // True if the URL should NOT be used for auto-complete.
+  optional bool hidden = 4;
+  // Timestamps for all visits to this URL.
+  repeated int64 visits = 7 [packed = true];
+  // The PageTransition::Type for each of the visits in the `visit` array. Both
+  // arrays must be the same length.
+  repeated int32 visit_transitions = 8 [packed = true];
+
+  reserved 3;
+  reserved "typed_count";
+  reserved 5;
+  reserved "visit";
+  reserved 6;
+  reserved "visited_count";
+}
diff --git a/pyhindsight/lib/components/sync/protocol/unencrypted_sharing_message.proto b/pyhindsight/lib/components/sync/protocol/unencrypted_sharing_message.proto
new file mode 100644
index 0000000..310eaac
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/unencrypted_sharing_message.proto
@@ -0,0 +1,71 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+package sync_pb;
+
+// Required in Chrome.
+option optimize_for = LITE_RUNTIME;
+
+// Message for sending between devices in Sharing. Messages defined here should
+// be set to the unencrypted_payload field of SharingMessageSpecifics.
+message UnencryptedSharingMessage {
+  // Identifier of sender.
+  optional string sender_guid = 1;
+
+  // Payload of the message, contains one of the messages below.
+  oneof payload {
+    SendTabToSelfPush send_tab_message = 2;
+  }
+
+  // The name of the device sending this message.
+  optional string sender_device_name = 3;
+}
+
+message SendTabToSelfPush {
+  // Required. Notification title text to display.
+  optional string title = 1;
+
+  // Required. Actual body text to display.
+  optional string text = 2;
+
+  message Image {
+    // Required. URL of this image resource. FIFE hosted URLs are preferred.
+    optional string url = 1;
+
+    // Optional. Alternate text to display if the image cannot be found and for
+    // accessibility reasons.
+    optional string alt_text = 2;
+  }
+
+  // Optional. An icon to be displayed alongside the notification, or a series
+  // of icons to be put in a collage. If no icon is specified, the frontend
+  // will display a generic icon image.
+  repeated Image icon = 3;
+
+  // Optional. A small app icon to display in certain notification views. This
+  // field can be omitted in favor of using a favicon specified in the
+  // chrome_chime client config. If this field is omitted and the client config
+  // favicon is unspecified, no icon is displayed.
+  optional Image favicon = 4;
+
+  // Required. A URL that will be visited when clicking on this notification.
+  optional string destination_url = 5;
+
+  // Placeholder title. Will be used if payload is not properly assembled on
+  // receiving device. Will not get encrypted by Chime.
+  optional string placeholder_title = 6;
+
+  // Placeholder body. Will be used if payload is not properly assembled on
+  // receiving device. Will not get encrypted by Chime.
+  optional string placeholder_body = 7;
+
+  // Unique identifier of the associated SendTabToSelfEntry. Will be used to
+  // dismiss the entry upon push notification interaction.
+  optional string entry_unique_guid = 8;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/unique_position.proto b/pyhindsight/lib/components/sync/protocol/unique_position.proto
new file mode 100644
index 0000000..361cde0
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/unique_position.proto
@@ -0,0 +1,82 @@
+// Copyright 2012 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Protobuf representation of the UniquePosition class.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// A UniquePosition is a string of bytes.
+//
+// Unique positions are unique per-item, since they are guaranteed to end with a
+// fixed-length suffix that is unique per-item.  The position string may not end
+// with a '\0' byte.
+//
+// Prior to the suffix is a series of arbitrary bytes of arbitrary length.
+// Items under the same parent are positioned relative to each other by a
+// lexicographic comparison of their UniquePosition values.
+message UniquePosition {
+  // History:
+  //
+  // Unique positions were first introduced in M28.  This change was rolled out
+  // in such a way that it would try to maintain backwards compatibilty with
+  // clients that understood only the old int64-based positions.
+  //
+  // At first, clients supported only the 'value' field.  This version never
+  // made it to stable.  We later added support for the 'compressed_value'
+  // field, and clients would populate either one or the other.
+  //
+  // In M30, we added the custom_compressed_v1 representation.  This
+  // representation was better than the previous implementations in almost every
+  // way.  However, we could not use it right away, since older clients would
+  // not understand it.  We decided to write both the old-style ('value' or
+  // 'custom_compressed') representation and the 'custom_compressed_v1'
+  // repersentations to every protobuf during the transition period.  Protobufs
+  // written during this transition period would be readable by clients who
+  // understand at least one of the two formats.
+  //
+  // In M33, we dropped support for writing the backwards-compatibility fields.
+  // Protobufs written by this version or later are not be intelligible by
+  // clients with version M29 or older.  Those clients will end up making use of
+  // the old int64 position fallback mechanism.
+
+  // The uncompressed string of bytes representing the position.
+  //
+  // Deprecated.  See history note above.
+  optional bytes value = 1 [deprecated = true];
+
+  // The client may choose to write a compressed position to this field instead
+  // of populating the 'value' above.  If it chooses to use compression, the
+  // 'value' field above must be empty.  The position value will be compressed
+  // with gzip and stored in the compressed_value field.  The position's
+  // uncompressed length must be specified and written to the
+  // uncompressed_length field.
+  //
+  // Deprecated.  See history note above.
+  optional bytes compressed_value = 2 [deprecated = true];
+  optional uint64 uncompressed_length = 3 [deprecated = true];
+
+  // This encoding uses compression scheme designed especially for unique
+  // positions.  It has the property that X < Y precisely when Compressed(X) <
+  // Compressed(Y), which is very useful when the most common operation is to
+  // compare these positions against each other.  Their values may remain
+  // compressed in memory.
+  //
+  // The compression scheme is implemented and documented in
+  // sync/core_impl/base/unique_position.cc.
+  //
+  // As of M30, this is the preferred encoding.  Newer clients may continue to
+  // populate the 'value' and 'compressed_value' fields to ensure backwards
+  // compatibility, but they will always try to read from this field first.
+  optional bytes custom_compressed_v1 = 4;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/user_consent_specifics.proto b/pyhindsight/lib/components/sync/protocol/user_consent_specifics.proto
new file mode 100644
index 0000000..91e3c92
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/user_consent_specifics.proto
@@ -0,0 +1,115 @@
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for user consents.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/user_consent_types.proto";
+
+// Next id: 18
+message UserConsentSpecifics {
+  // ===========================================================================
+  // Fields common to all Chrome User Consents.
+  // ===========================================================================
+
+  // The UI language Chrome is using, represented as the IETF language tag
+  // defined in BCP 47. The region subtag is not included when it adds no
+  // distinguishing information to the language tag (e.g. both "en-US"
+  // and "fr" are correct here).
+  optional string locale = 4;
+
+  // The local time on the client when the user consent was recorded. The time
+  // as measured by client is given in microseconds since Windows epoch. This
+  // is needed since user consent recording may happen when a client is
+  // offline.
+  optional int64 client_consent_time_usec = 12;
+
+  // ===========================================================================
+  // The specific consent type. Add new User Consent types to
+  // user_consent_types.proto.
+  // ===========================================================================
+
+  oneof consent {
+    UserConsentTypes.SyncConsent sync_consent = 7;
+
+    UserConsentTypes.ArcBackupAndRestoreConsent arc_backup_and_restore_consent =
+        8;
+
+    UserConsentTypes.ArcGoogleLocationServiceConsent
+        arc_location_service_consent = 9;
+
+    UserConsentTypes.ArcPlayTermsOfServiceConsent
+        arc_play_terms_of_service_consent = 10;
+
+    UserConsentTypes.UnifiedConsent unified_consent = 13 [deprecated = true];
+
+    UserConsentTypes.AssistantActivityControlConsent
+        assistant_activity_control_consent = 14 [deprecated = true];
+
+    UserConsentTypes.AccountPasswordsConsent account_passwords_consent = 15
+        [deprecated = true];
+
+    UserConsentTypes.RecorderSpeakerLabelConsent
+        recorder_speaker_label_consent = 17;
+  }
+  reserved "arc_metrics_and_usage_consent";
+  reserved 11;
+  reserved "autofill_assistant_consent";
+  reserved 16;
+
+  // ===========================================================================
+  // Client only fields.
+  // ===========================================================================
+  // TODO(markusheintz): Refactor the code so that these fields can be moved out
+  // of this message.
+
+  // The obfuscated Gaia ID of the user who gave the consent. This field is used
+  // by UserEventService to distinguish consents from different users,
+  // as UserConsent does not get deleted when a user signs out. However,
+  // it should be cleared before being sent over the wire, as the UserEvent
+  // is sent over an authenticated channel, so this information would be
+  // redundant.
+  //
+  // For semantics and usage of the `obfuscated_gaia_id` in the signin codebase,
+  // see IdentityManager::GetPrimaryAccountInfo() or GaiaId.
+  optional string obfuscated_gaia_id = 6;
+
+  // ===========================================================================
+  // Deprecated fields. Please do not use them!
+  // They have to remain in the proto because the server must continue
+  // supporting legacy consent formats like this.
+  // ===========================================================================
+
+  // Which feature does the consent apply to?
+  enum Feature {
+    FEATURE_UNSPECIFIED = 0;
+    CHROME_SYNC = 1;
+    PLAY_STORE = 2;
+    BACKUP_AND_RESTORE = 3;
+    GOOGLE_LOCATION_SERVICE = 4;
+    CHROME_UNIFIED_CONSENT = 5;
+    // TODO(markusheintz): ASSISTANT_ACTIVITY_CONTROL was only added for
+    // compatibility with the Feature enum in UserEventSpecifics.UserConsent.
+    // Delete this value once the value is deleted from the other proto.
+    ASSISTANT_ACTIVITY_CONTROL = 6;
+  }
+  optional Feature feature = 1 [deprecated = true];
+  // Ids of the strings of the consent text presented to the user.
+  repeated int32 description_grd_ids = 2 [deprecated = true];
+  // Id of the string of the UI element the user clicked when consenting.
+  optional int32 confirmation_grd_id = 3 [deprecated = true];
+  // Was the consent for `feature` given or not given (denied/revoked)?
+  optional UserConsentTypes.ConsentStatus status = 5 [deprecated = true];
+}
diff --git a/pyhindsight/lib/components/sync/protocol/user_consent_types.proto b/pyhindsight/lib/components/sync/protocol/user_consent_types.proto
new file mode 100644
index 0000000..315b2e0
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/user_consent_types.proto
@@ -0,0 +1,188 @@
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Various user consent types used when reporting consent.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message UserConsentTypes {
+  // The status of a particular User Consent. The status describes the state
+  // of the consent as it is: given, not_given.
+  enum ConsentStatus {
+    // The status is unspecified e.g. because the user was not asked to
+    // consent yet or an error happened or the decision was delayed.
+    CONSENT_STATUS_UNSPECIFIED = 0;
+    // The consent is not given. This means the user either revoked the
+    // consent or did not grant it in the first place.
+    NOT_GIVEN = 1;
+    // The consent is given. This means the user did grant the consent.
+    GIVEN = 2;
+  }
+
+  // ===========================================================================
+  // Keep sorted alphabetically.
+  // Don't forget to update proto_visitors.h and potentially
+  // proto_enum_conversions.{h, cc}. Never TBR proto changes, because they need
+  // to be manually imported on the Sync server.
+  // ===========================================================================
+
+  // The user consent for the ARC Backup And Restore feature. The consent
+  // status is determined by the corresponding setting on the ARC setup dialog.
+  message ArcBackupAndRestoreConsent {
+    // Ids of the strings of the setting text presented to the user.
+    repeated int32 description_grd_ids = 1;
+
+    // Id of the string of the UI element the user clicked when consenting.
+    optional int32 confirmation_grd_id = 2;
+
+    optional ConsentStatus status = 3;
+  }
+
+  // The user consent for the Google Location Service. The consent status is
+  // determined by the corresponding setting on the ARC setup dialog.
+  message ArcGoogleLocationServiceConsent {
+    // Ids of the strings of the setting text presented to the user.
+    repeated int32 description_grd_ids = 1;
+
+    // Id of the string of the UI element the user clicked when consenting.
+    optional int32 confirmation_grd_id = 2;
+
+    optional ConsentStatus status = 3;
+  }
+
+  // The user consent for the Play terms of service is determined by the user
+  // action on the ARC setup dialog that presents the Play Terms of Service.
+  message ArcPlayTermsOfServiceConsent {
+    // The length of the UTF-8 encoded string of the Play Terms of Service
+    // text. The length is given in number of bytes.
+    optional int32 play_terms_of_service_text_length = 1;
+
+    // The SHA1 hash of UTF-8 encoded string of the Play Terms of Service
+    // displayed to the user.
+    optional bytes play_terms_of_service_hash = 2;
+
+    // GRD Ids of the strings on the consent UI that was shown to the user.
+    repeated int32 description_grd_ids = 5;
+
+    // Id of the string of the UI element the user clicked when consenting.
+    optional int32 confirmation_grd_id = 3;
+
+    // The status of the Play Terms of Service consent. This specifies whether
+    // the consent was given or not given/revoked.
+    optional ConsentStatus status = 4;
+
+    // Enum describing different user flow during which the ARC Play Terms of
+    // service consent can be recorded.
+    enum ConsentFlow {
+      // The ARC setup flow on a CROS device.
+      SETUP = 1;
+      // The user flow for changing the ARC setting on a CROS device.
+      SETTING_CHANGE = 2;
+    }
+    // The user flow during which the consent was recorded. This is necessary in
+    // order to create the correct UI context and Event for the backend.
+    optional ConsentFlow consent_flow = 6;
+  }
+
+  // The User Consent for Chrome Sync is determined by the user action on the
+  // corresponding Sync Consent dialog.
+  message SyncConsent {
+    // Ids of the strings of the sync consent text presented to the user.
+    repeated int32 description_grd_ids = 1;
+
+    // Id of the string of the UI element the user clicked in order to confirm
+    // and close the sync consent dialog.
+    optional int32 confirmation_grd_id = 2;
+
+    // The status of the sync consent. This specifies whether the consent was
+    // given or not given/revoked.
+    optional ConsentStatus status = 3;
+  }
+
+  // The unified User Consent for Chrome is determined by the user action on the
+  // corresponding Chrome Consent dialog.
+  message UnifiedConsent {
+    // Ids of the strings of the unified Chrome consent text presented to the
+    // user.
+    repeated int32 description_grd_ids = 1;
+
+    // Id of the string of the UI element the user clicked in order to confirm
+    // and close the unified Chrome consent dialog.
+    optional int32 confirmation_grd_id = 2;
+
+    // The status of the unified Chrome consent. This specifies whether the
+    // consent was given or not given/revoked.
+    optional ConsentStatus status = 3;
+  }
+
+  // The User Consent for Assistant activity control is determined by the user
+  // action on the Assistant opt-in flow.
+  message AssistantActivityControlConsent {
+    // An opaque token to for ui auditing, which strengthens the audit trail.
+    optional bytes ui_audit_key = 1;
+
+    // The status of the Assistant activity control consent. This specifies
+    // whether the consent was given or not given.
+    optional ConsentStatus status = 2;
+
+    // Enum denoting different Assistant activity control setting type.
+    enum SettingType {
+      // Legacy clients (< M93) did not set a SettingType; for those,
+      // UNSPECIFIED should be interpreted as ALL. Newer clients should always
+      // set it explicitly.
+      SETTING_TYPE_UNSPECIFIED = 0;
+      // All Settings.
+      ALL = 1;
+      WEB_AND_APP_ACTIVITY = 2;
+      DEVICE_APPS = 3;
+    }
+
+    // The activity control setting which the consent was given or not given to.
+    // Clients before M93 did not set this field. Such consents should be
+    // treated as applying to ALL.
+    optional SettingType setting_type = 3;
+  }
+
+  // The User Consent for downloading and using passwords stored in the user's
+  // Google Account. Determined during the opt-in flow for the feature.
+  message AccountPasswordsConsent {
+    // Ids of the strings of the consent text presented to the user.
+    repeated int32 description_grd_ids = 1;
+
+    // Id of the string of the UI element the user clicked in order to confirm
+    // the consent dialog.
+    optional int32 confirmation_grd_id = 2;
+
+    // The status of the consent. This specifies whether the consent was given
+    // or not given/revoked.
+    optional ConsentStatus status = 3;
+  }
+
+  // The User Consent for enabling or disabling speaker label feature in
+  // Recorder app.
+  message RecorderSpeakerLabelConsent {
+    // Ids of the strings of the Recorder speaker label consent text presented
+    // to the user.
+    repeated int32 description_grd_ids = 1;
+
+    // Id of the string of the UI element the user clicked in order to give or
+    // not give the consent and close the Recorder speaker label consent
+    // dialog.
+    optional int32 confirmation_grd_id = 2;
+
+    // The status of the Recorder speaker label consent. This specifies whether
+    // the consent was given or not given/revoked.
+    optional ConsentStatus status = 3;
+  }
+}
diff --git a/pyhindsight/lib/components/sync/protocol/user_event_specifics.proto b/pyhindsight/lib/components/sync/protocol/user_event_specifics.proto
new file mode 100644
index 0000000..8032cb4
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/user_event_specifics.proto
@@ -0,0 +1,140 @@
+// Copyright 2017 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for user events.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/gaia_password_reuse.proto";
+
+message UserEventSpecifics {
+  // Time of event, as measured by client in microseconds since Windows epoch.
+  optional int64 event_time_usec = 1;
+
+  // The `global_id` field of the associated navigation, if there is one.
+  optional int64 navigation_id = 2;
+
+  // On startup we generate a new random id to identify which FieldTrialEvents
+  // other events belonged to.
+  optional fixed64 session_id = 3;
+
+  // 4-7 reserved for future scalars.
+
+  // Used for testing and debugging EventLog system.
+  message Test {}
+
+  // Language detection output.
+  message LanguageDetection {
+    option deprecated = true;
+
+    message Language {
+      // ISO 639 language code will be used.
+      optional string language_code = 1;
+      // Whether the detected language is reliable, note this is determined by
+      // the CLD3.
+      optional bool is_reliable = 2;
+    }
+    // Top n languages. Typically we just log the top language, but for page
+    // that we're not confident about, we may log up to 3 top languages in
+    // descending order.
+    repeated Language detected_languages = 1;
+    // Adopted language code is the code of final determined language.
+    // It will be stored only if it's different from the first detected
+    // language.
+    optional string adopted_language_code = 2;
+  }
+
+  // User translated a page or interacted with translate suggestion.
+  message Translation {
+    option deprecated = true;
+
+    // Source language of the translation.
+    optional string from_language_code = 1;
+    // Target language of the translation.
+    optional string to_language_code = 2;
+    enum Interaction {
+      UNKNOWN = 0;
+      ACCEPT = 1;
+      DECLINE = 2;
+      // This happens when user scroll or click outside the UI without
+      // translation.
+      IGNORED = 3;
+      // This happens when user choose to close the translation window without
+      // translation.
+      DISMISSED = 4;
+      // User manually entered either language.
+      // In this case, from_language_code and to_language_code will be user
+      // chosen values.
+      MANUAL = 5;
+      // User choose to revert the translation, in this case, from_language_code
+      // and to_language_code will be previous chosen values.
+      TRANSLATION_REVERTED = 6;
+      // Automatically triggered translation.
+      // User sets always translate in user settings.
+      AUTO_TRANSLATION_BY_PREF = 7;
+      // User navigated through a click from a translated page.
+      AUTO_TRANSLATION_BY_LINK = 8;
+      // Failed to initialize the translate script, this can happen for iOS due
+      // to CSPs.
+      INITIALIZATION_ERROR = 9;
+    }
+    optional Interaction interaction = 3;
+  }
+
+  // Logged when the user logs into Google, and at least once per 28d.
+  message GaiaPasswordCaptured {
+    enum EventTrigger {
+      UNSPECIFIED = 0;
+      // Event added because user logged in.
+      USER_LOGGED_IN = 1;
+      // Event added because 28d timer fired.
+      EXPIRED_28D_TIMER = 2;
+    }
+    optional EventTrigger event_trigger = 1;
+  }
+
+  message FlocIdComputed {
+    enum EventTrigger {
+      UNSPECIFIED = 0;
+      // Event added because the floc id is computed for the 1st floc session.
+      NEW = 1;
+      // Event added because the floc id is re-computed due to a long period of
+      // time has passed since the last computation.
+      REFRESHED = 2;
+      // Event added because the floc id is re-computed due to history deletion.
+      HISTORY_DELETE = 3;
+    }
+    reserved 1;
+    reserved "event_trigger";
+
+    // If not set, it means that the floc is disabled.
+    optional uint64 floc_id = 2;
+  }
+
+  oneof event {
+    Test test_event = 8;
+    LanguageDetection language_detection_event = 10 [deprecated = true];
+    Translation translation_event = 11 [deprecated = true];
+    // Happens when a user types their Google account password on another site.
+    GaiaPasswordReuse gaia_password_reuse_event = 104;
+    GaiaPasswordCaptured gaia_password_captured_event = 15;
+    FlocIdComputed floc_id_computed_event = 16;
+  }
+
+  reserved "field_trial_event";
+  reserved 9;
+
+  reserved "user_consent";
+  reserved 12;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/web_apk_specifics.proto b/pyhindsight/lib/components/sync/protocol/web_apk_specifics.proto
new file mode 100644
index 0000000..3537487
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/web_apk_specifics.proto
@@ -0,0 +1,50 @@
+// Copyright 2023 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update
+// components/sync/protocol/proto_visitors.h and potentially
+// components/sync/protocol/proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Sync & local data: Information about web app icon.
+message WebApkIconInfo {
+  enum Purpose {
+    UNSPECIFIED = 0;
+    // Suitable for any purpose.
+    ANY = 1;
+    // Designed for masking.
+    MASKABLE = 2;
+    // Suitable for monochrome purposes.
+    MONOCHROME = 3;
+  }
+
+  // The size of the square app icon, in raw pixels.
+  optional int32 size_in_px = 1;
+  // The URL of the app icon.
+  optional string url = 2;
+  // The purpose or context in which the icon should be used.
+  optional Purpose purpose = 3;
+}
+
+// WebApk data.
+message WebApkSpecifics {
+  optional string manifest_id = 1;
+  optional string start_url = 2;
+  optional string name = 3;
+  optional uint32 theme_color = 4;
+  optional string scope = 5;
+  repeated WebApkIconInfo icon_infos = 6;
+
+  // Time when this WebApk was last used or installed.
+  // Number of microseconds since 1601, aka Windows epoch.
+  optional int64 last_used_time_windows_epoch_micros = 7;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/web_app_specifics.proto b/pyhindsight/lib/components/sync/protocol/web_app_specifics.proto
new file mode 100644
index 0000000..211721d
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/web_app_specifics.proto
@@ -0,0 +1,103 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update
+// components/sync/protocol/proto_visitors.h and potentially
+// components/sync/protocol/proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// Sync & local data: Information about web app icon.
+message WebAppIconInfo {
+  enum Purpose {
+    UNSPECIFIED = 0;
+    // Suitable for any purpose.
+    ANY = 1;
+    // Designed for masking.
+    MASKABLE = 2;
+    // Suitable for monochrome purposes.
+    MONOCHROME = 3;
+  }
+
+  // The size of the square app icon, in raw pixels.
+  optional int32 size_in_px = 1;
+  // The URL of the app icon.
+  optional string url = 2;
+  // The purpose or context in which the icon should be used.
+  optional Purpose purpose = 3;
+}
+
+// WebApp data. This is a synced part of
+// chrome/browser/web_applications/proto/web_app.proto data.
+// Note: Pre-M125 clients will incorrectly drop any unrecognized new fields
+// added to the proto. Handling should be added to ApplySyncDataToApp in
+// web_app_sync_bridge.cc if new fields need to be preserved.
+message WebAppSpecifics {
+  // This enum should be a subset of the DisplayMode enum in
+  // chrome/browser/web_applications/proto/web_app.proto and
+  // third_party/blink/public/mojom/manifest/display_mode.mojom
+  enum UserDisplayMode {
+    UNSPECIFIED = 0;
+    BROWSER = 1;
+    // MINIMAL_UI is never serialized.
+    STANDALONE = 3;
+    // FULLSCREEN is never serialized.
+    // WINDOW_CONTROLS_OVERLAY is never serialized.
+    TABBED = 6;
+    // BORDERLESS is never serialized.
+    // PICTURE_IN_PICTURE is never serialized.
+  }
+
+  optional string start_url = 1;
+  optional string name = 2;
+
+  // User-selected display setting, which may be used if no platform-specific
+  // setting is available (eg. on Windows, Mac, and Linux). If absent,
+  // user_display_mode_cros may be used as fallback (if populated). On pre-M122
+  // devices this field is used by all platforms (ie. ChromeOS, Windows, Mac,
+  // Linux) and always replaces any locally-stored value, with
+  // absent/unspecified falling back to standalone.
+  optional UserDisplayMode user_display_mode_default = 3;
+  reserved "user_display_mode_non_cros";
+  reserved "user_display_mode";
+
+  optional uint32 theme_color = 4;
+  optional string scope = 5;
+  repeated WebAppIconInfo icon_infos = 6;
+
+  // Used to store the page number that the app is displayed on in
+  // chrome://apps.
+  optional string user_page_ordinal = 7;
+  // Used to store the in-page ranking for ordering apps in its given
+  // `user_page_ordinal` page.
+  optional string user_launch_ordinal = 8;
+
+  // Used to store id specified in the manifest. This is a path that is relative
+  // to the start_url, similar to how the id field is parsed in
+  // https://www.w3.org/TR/appmanifest/#id-member, except this field does not
+  // include a scheme or origin. This is only the path after the origin,
+  // excluding the first "/".
+  // Note: If this field is not set, then the manifest_id is generated using the
+  // start_url in GenerateManifestIdFromStartUrlOnly. This is different than if
+  // this is set to "", which means the manifest_id will be set to the origin of
+  // the start_url.
+  optional string relative_manifest_id = 9;
+
+  // User-selected display setting for ChromeOS.
+  // If absent, user_display_mode_default may be used as fallback (if
+  // populated).
+  // Introduced in M122.
+  optional UserDisplayMode user_display_mode_cros = 10;
+
+  // Contains the metadata for the trusted icons to be shown on security
+  // sensitive surfaces by the web app.
+  repeated WebAppIconInfo trusted_icons = 11;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/webauthn_credential_specifics.proto b/pyhindsight/lib/components/sync/protocol/webauthn_credential_specifics.proto
new file mode 100644
index 0000000..24ae1ab
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/webauthn_credential_specifics.proto
@@ -0,0 +1,199 @@
+// Copyright 2021 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+// WebauthnCredentialSpecifics is an entity that backs a WebAuthn
+// PublicKeyCredential. Since it contains the authenticator’s view of this
+// object, it has a private key rather than a public key.
+// (https://www.w3.org/TR/webauthn-2/#iface-pkcredential).
+//
+// Names of fields are taken from WebAuthn where possible. E.g.
+// user.displayName in WebAuthn becomes user_display_name here.
+//
+// All fields are immutable after creation except for user_name and
+// user_display_name, which may be updated by a user.
+message WebauthnCredentialSpecifics {
+  // Sync's ID for this entity (sometimes called the client unique tag), 16
+  // random bytes. This value is used within Sync to identify this entity. The
+  // credential ID is not used because the (hashed) sync_id is exposed to the
+  // Sync server, and we don’t want Google to be able to map a credential ID to
+  // an account. Password entities construct this value from the concatenation
+  // of many fields and depend on the fact that the server only sees a hash of
+  // it. But the only high-entropy secret here is the private key, which will
+  // have different encryption in the future, and private keys are not the sort
+  // of data to copy into other fields. Therefore this independent value is
+  // provided to form the client's ID.
+  optional bytes sync_id = 1;
+
+  // The credential ID, 16 random bytes. This is a value surfaced in
+  // the WebAuthn API (https://www.w3.org/TR/webauthn-2/#credential-id).
+  optional bytes credential_id = 2;
+
+  // An RP ID is a WebAuthn concept:
+  // https://www.w3.org/TR/webauthn-2/#rp-id. It’s usually a domain name,
+  // although in non-Web contexts it can be a URL with a non-Web scheme.
+  optional string rp_id = 3;
+
+  // The user ID, which is also called a “user handle” in WebAuthn
+  // (https://www.w3.org/TR/webauthn-2/#user-handle), is an RP-specific
+  // identifier that is up to 64-bytes long. An authenticator conceptually only
+  // stores a single credential for a given (rp_id, user_id) pair, but there
+  // may be several credentials in Sync. They are prioritised using
+  // newly_shadowed_credential_ids and creation_time. See below.
+  //
+  // (We wish to be able to retain several entities for a single (rp_id,
+  // user_id) pair because there’s an edge case where we may wish to revert to
+  // an older entry and thus need to keep the older entry around in Sync. The
+  // revert could happen on a different device too.)
+  optional bytes user_id = 4;
+
+  // The id of credentials with the same (rp_id, user_id) that were
+  // shadowed by the creation of this entity.
+  //
+  // A credential is shadowed if one or more other credentials (from the same
+  // account, and with the same (rp_id, user_id)) include its credential_id in
+  // their list of shadowed IDs. Shadowed credentials are ignored when finding
+  // a credential to sign with. If there is more than one candidate remaining
+  // after filtering shadowed credentials then the most recently created (based
+  // on creation_time) is used.
+  //
+  // The reason for all this is that sites can replace a credential by creating
+  // another one with the same (rp_id, user_id) pair. However, we don't
+  // immediately know whether the WebAuthn response reached the website's
+  // server. Consider a user with a poor internet connection. Javascript in the
+  // site's origin triggers a credential creation that “overwrites” an existing
+  // credential, but the Javascript is unable to send the new public key to the
+  // website's server. The user is now locked out: the old credential has been
+  // over-written but the website's server doesn't know about the new one.
+  //
+  // Thus we wish to keep “overwritten” credentials around for a while to allow
+  // for some sort of recovery. In the simple case, a new credential shadows
+  // the single, previous old credential. We could depend on creation_time, but
+  // client clocks aren't always accurate, thus this field.
+  //
+  // In complicated cases two devices might race to replace a credential, in
+  // which case (after mutual syncing) two candidate credentials exist for the
+  // same (rp_id, user_id) pair because neither shadows the other. In this case
+  // we pick the newest based on `creation_time` but it's quite possible that
+  // some recovery will be needed because the website's server thinks the other
+  // one is correct.
+  //
+  // A generation counter isn't used because a single device might replace a
+  // series of credentials as it tries to update the website's server. But that
+  // doesn't mean that it should dominate a different device that replaced it
+  // only once, but later.
+  repeated bytes newly_shadowed_credential_ids = 5;
+
+  // The local time on the device when this credential was created. Given in
+  // milliseconds since the UNIX epoch. This is used to break ties between
+  // credentials. See newly_shadowed_credential_ids.
+  optional int64 creation_time = 6;
+
+  // The human-readable account identifier. Usually an email address. This is
+  // mutable.
+  // https://www.w3.org/TR/webauthn-2/#dom-publickeycredentialentity-name
+  optional string user_name = 7;
+
+  // The human-readable name. Usually a legal name. This is mutable.
+  // https://www.w3.org/TR/webauthn-2/#dom-publickeycredentialuserentity-displayname.
+  optional string user_display_name = 8;
+
+  // Reserving obsolete field.
+  reserved 10;
+
+  // Credentials may optionally be enabled for Secure Payment Confirmation[1] on
+  // third-party sites. This is opt-in at creation time.
+  //
+  // [1] https://www.w3.org/TR/secure-payment-confirmation/
+  optional bool third_party_payments_support = 11;
+
+  // Time when this passkey was last successfully asserted. Number of
+  // microseconds since 1601, aka Windows epoch. This mirrors the
+  // `date_last_used` field in PasswordSpecificsData.
+  optional int64 last_used_time_windows_epoch_micros = 13;
+
+  message Encrypted {
+    // The bytes of the private key, in PKCS#8 format.
+    optional bytes private_key = 1;
+
+    // The secret for implementing the hmac-secret extension
+    // https://fidoalliance.org/specs/fido-v2.1-ps-20210615/fido-client-to-authenticator-protocol-v2.1-ps-errata-20220621.html#sctn-hmac-secret-extension
+    optional bytes hmac_secret = 2;
+
+    // The contents of the credential's credBlob.
+    // https://fidoalliance.org/specs/fido-v2.1-ps-20210615/fido-client-to-authenticator-protocol-v2.1-ps-errata-20220621.html#sctn-credBlob-extension
+    optional bytes cred_blob = 3;
+
+    // The contents of the credential's largeBlob value(*). Unlike with security
+    // keys, largeBlob data is not stored in a single lump for all credentials,
+    // but as per-credential data. This data is presented to the authenticator
+    // over CTAP and thus has already had the required DEFLATE compression
+    // applied by the remote platform. The uncompressed size of this data is in
+    // the next field.
+    //
+    // (*) "large" with respect to embedded devices. Maximum length is 2KiB for
+    // Google Password Manager.
+    //
+    // https://fidoalliance.org/specs/fido-v2.1-ps-20210615/fido-client-to-authenticator-protocol-v2.1-ps-errata-20220621.html#authenticatorLargeBlobs
+    optional bytes large_blob = 4;
+
+    // The claimed uncompressed size of the DEFLATE-compressed data in
+    // `large_blob`. This corresponds to the `origSize` field from the spec:
+    // https://fidoalliance.org/specs/fido-v2.1-ps-20210615/fido-client-to-authenticator-protocol-v2.1-ps-errata-20220621.html#large-blob
+    optional uint64 large_blob_uncompressed_size = 5;
+  }
+
+  message SecurityDomainEncrypted {
+    // A serialized `Encrypted` message, encrypted with the device authorization
+    // key (see `device_authorization_key_version` for the key version).
+    optional bytes device_authorization_encrypted = 1;
+  }
+
+  // The "version" (sometimes called the epoch) of the key that `encrypted_data`
+  // is encrypted with. This allows trial decryption to be avoided when present.
+  optional int32 key_version = 14;
+
+  // The key version of the device authorization key that
+  // `device_authorization_encrypted` in `SecurityDomainEncrypted` is encrypted
+  // with.
+  optional int32 device_authorization_key_version = 18;
+
+  oneof encrypted_data {
+    // The bytes of the private key, encrypted with a feature-specific security
+    // domain.
+    bytes private_key = 9;
+
+    // A serialized, `Encrypted` message, encrypted with a feature-specific
+    // security domain.
+    bytes encrypted = 12;
+
+    // A serialized `SecurityDomainEncrypted` message, encrypted with a
+    // feature-specific security domain key.
+    bytes security_domain_encrypted = 19;
+  }
+
+  // `edited_by_user` is set to `true` the first time a user manually changes
+  // the credential's `user_name` or `user_display_name`.
+  optional bool edited_by_user = 15;
+
+  // `hidden` is set to `true` if the credential should not be shown on
+  // authentication surfaces, e.g. because a site marked it as obsolete.
+  optional bool hidden = 16;
+
+  // The local time on the device when this credential was hidden. Given in
+  // milliseconds since the UNIX epoch. This is used to permanently delete
+  // credentials after they've been hidden for a while.
+  optional int64 hidden_time = 17;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/wifi_configuration_specifics.proto b/pyhindsight/lib/components/sync/protocol/wifi_configuration_specifics.proto
new file mode 100644
index 0000000..911d7c1
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/wifi_configuration_specifics.proto
@@ -0,0 +1,92 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for Wi-Fi configuration items.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+message WifiConfigurationSpecifics {
+  // SSID encoded to hex, letters should be upper case and 0x prefix should be
+  // omitted. For example, ssid "network" would be provided as "6E6574776F726B".
+  optional bytes hex_ssid = 1;
+  enum SecurityType {
+    SECURITY_TYPE_UNSPECIFIED = 0;
+    SECURITY_TYPE_NONE = 1;
+    SECURITY_TYPE_WEP = 2;
+    SECURITY_TYPE_PSK = 3;  // WPA-PSK or RSN-PSK
+  }
+  optional SecurityType security_type = 2;
+  // The passphrase can be ASCII, UTF-8, or a string of hex digits.
+  optional bytes passphrase = 3;
+  enum AutomaticallyConnectOption {
+    AUTOMATICALLY_CONNECT_UNSPECIFIED = 0;
+    AUTOMATICALLY_CONNECT_DISABLED = 1;
+    AUTOMATICALLY_CONNECT_ENABLED = 2;
+  }
+  optional AutomaticallyConnectOption automatically_connect = 4;
+  enum IsPreferredOption {
+    IS_PREFERRED_UNSPECIFIED = 0;
+    IS_PREFERRED_DISABLED = 1;
+    IS_PREFERRED_ENABLED = 2;
+  }
+  optional IsPreferredOption is_preferred = 5;
+  enum MeteredOption {
+    METERED_OPTION_UNSPECIFIED = 0;
+    METERED_OPTION_NO = 1;
+    METERED_OPTION_YES = 2;
+    // Allows the device to use heuristics to determine if network is metered.
+    METERED_OPTION_AUTO = 3;
+  }
+  optional MeteredOption metered = 6;
+  message ProxyConfiguration {
+    enum ProxyOption {
+      PROXY_OPTION_UNSPECIFIED = 0;
+      PROXY_OPTION_DISABLED = 1;
+      // Use a Proxy Auto-config(PAC) Url, set in proxy_url
+      PROXY_OPTION_AUTOMATIC = 2;
+      // Uses Web Proxy Auto-Discovery Protocol (WPAD) to discover the proxy
+      // settings using DHCP/DNS.
+      PROXY_OPTION_AUTODISCOVERY = 3;
+      // User sets details in manual_proxy_configuration.
+      PROXY_OPTION_MANUAL = 4;
+    }
+    optional ProxyOption proxy_option = 1;
+    // Only set if PROXY_OPTION_AUTOMATIC.
+    optional string autoconfiguration_url = 2;
+    message ManualProxyConfiguration {
+      optional string http_proxy_url = 1;
+      optional int32 http_proxy_port = 2;
+      optional string secure_http_proxy_url = 3;
+      optional int32 secure_http_proxy_port = 4;
+      optional string socks_host_url = 5;
+      optional int32 socks_host_port = 6;
+      repeated string excluded_domains = 7;
+    }
+    // Only set if PROXY_OPTION_MANUAL.
+    optional ManualProxyConfiguration manual_proxy_configuration = 3;
+  }
+  optional ProxyConfiguration proxy_configuration = 7;
+  enum DnsOption {
+    DNS_OPTION_UNSPECIFIED = 0;
+    DNS_OPTION_DEFAULT_DHCP = 1;
+    DNS_OPTION_CUSTOM = 2;
+  }
+  optional DnsOption dns_option = 10;
+  // List of DNS servers to be used when set to DNS_OPTION_CUSTOM.  Up to 4.
+  repeated string custom_dns = 8;
+  // The last time this configuration was connected to before being synced.  It
+  // will only be updated when the configuration is changed. This is represented
+  // with the UNIX timestamp, ms since epoch.
+  optional int64 last_connected_timestamp = 9;
+}
diff --git a/pyhindsight/lib/components/sync/protocol/workspace_desk_specifics.proto b/pyhindsight/lib/components/sync/protocol/workspace_desk_specifics.proto
new file mode 100644
index 0000000..4f7cd39
--- /dev/null
+++ b/pyhindsight/lib/components/sync/protocol/workspace_desk_specifics.proto
@@ -0,0 +1,309 @@
+// Copyright 2021 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for desks on Chrome OS.
+
+// If you change or add any fields in this file, update proto_visitors.h and
+// potentially proto_enum_conversions.{h, cc}.
+
+syntax = "proto2";
+
+option java_multiple_files = true;
+option java_package = "org.chromium.components.sync.protocol";
+
+option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "components/sync/protocol/sync_enums.proto";
+
+// A workspace desk entry. This proto contains the fields synced to represent
+// a saved desk in user's workspace.
+message WorkspaceDeskSpecifics {
+  reserved "created_time_usec";
+
+  // A random unique identifier for each desk.
+  // Required.
+  optional string uuid = 1;
+  // The name of the desk being saved.
+  optional string name = 2;
+  // The time this snapshot of desk was created.
+  optional int64 created_time_windows_epoch_micros = 3;
+
+  // The time this snapshot of desk was updated.
+  optional int64 updated_time_windows_epoch_micros = 5;
+
+  optional Desk desk = 4;
+
+  // The type of a desk.
+  optional DeskType desk_type = 6;
+
+  // The cache guid of the syncing client. Used to identify a unique device
+  // that's syncing data.
+  optional string client_cache_guid = 7;
+
+  // The form factor of the device.
+  optional SyncEnums.DeviceFormFactor device_form_factor = 8;
+
+  // The list of Coral tab and app entities.
+  optional CoralTabAppEntities coral_tab_app_entities = 9;
+
+  // Represent a snapshot of the information on a desk.
+  message Desk {
+    // The apps in this template.
+    repeated App apps = 1;
+  }
+
+  // A Launchable app in template.
+  message App {
+    // The on-display location of this window.
+    optional WindowBound window_bound = 1;
+    optional WindowState window_state = 2;
+    // The z-index of this app relative to other apps in this template.
+    // App with larger z-index appears in front of app with smaller z-index.
+    optional int32 z_index = 3;
+
+    optional AppOneOf app = 4;
+
+    // window_id used to instantiate proto as a restore_data object.  The
+    // restore_data object in question can be found at:
+    // //components/app_restore/restore_data.h
+    optional int32 window_id = 5;
+
+    // Display ID this app is on.
+    optional int64 display_id = 6;
+
+    // State of a window before it was minimized. Empty/unset for non-minimized
+    // windows.
+    optional WindowState pre_minimized_window_state = 7;
+
+    // Container this app was launched from.  Empty/unset for Arc apps.
+    optional LaunchContainer container = 8;
+
+    // Window open disposition, defines how a window opens. Empty/unset for Arc
+    // apps.
+    optional WindowOpenDisposition disposition = 9;
+
+    // Name of the app which is used by the browser to determine whether to
+    // launch an app as an app or a tab. Does not contain a human readable name
+    // but contains the app ID and a prefix.
+    optional string app_name = 10;
+
+    // Human readable title of the app.
+    optional string title = 11;
+
+    // This is used to determine the size of a snapped window is in clamshell
+    // mode. Empty/unset for non-snapped windows. This should be a value between
+    // 0 and 100.
+    optional int32 snap_percentage = 12;
+
+    // The override URL can be specified by apps to override the default URL at
+    // launch.
+    optional string override_url = 13;
+  }
+
+  message AppOneOf {
+    oneof app {
+      BrowserAppWindow browser_app_window = 1;
+      ChromeApp chrome_app = 2;
+      ProgressiveWebApp progress_web_app = 3;
+      ArcApp arc_app = 4;
+    }
+  }
+
+  // A Chrome or Lacros Browser app window.
+  message BrowserAppWindow {
+    message BrowserAppTab {
+      // The last committed URL of the main frame of the tab.
+      optional string url = 1;
+      // The title of the tab.
+      optional string title = 2;
+    }
+
+    // Structure representing a tab group associated with this window.
+    message TabGroup {
+      // Zero-based index within the browser app tabs of the first tab in the
+      // group.
+      optional int32 first_index = 1;
+
+      // Zero-based Index wotjom the browser app tabs of the last tab in the
+      // group.
+      optional int32 last_index = 2;
+
+      // User readable title of the tab group.
+      optional string title = 3;
+
+      // Color associated with this tab group.
+      optional TabGroupColor color = 4;
+
+      // Indicates whether the tab group is collapsed.
+      optional bool is_collapsed = 5;
+    }
+
+    // The tabs in this browser window.
+    repeated BrowserAppTab tabs = 1;
+
+    // The index of the currently active tab.
+    optional int32 active_tab_index = 2;
+
+    // Indicates whether to show as a dedicated app window.
+    optional bool show_as_app = 3;
+
+    // Tab groups associated with this window.
+    repeated TabGroup tab_groups = 4;
+
+    // The index of the first non-pinned tab.
+    optional int32 first_non_pinned_tab_index = 5;
+  }
+
+  // A Chrome App window.
+  message ChromeApp {
+    // The Chrome App's App ID.
+    optional string app_id = 1;
+
+    reserved 2;
+  }
+
+  // A PWA window.
+  message ProgressiveWebApp {
+    // The PWA's App ID.
+    optional string app_id = 1;
+
+    reserved 2;
+  }
+
+  // An Arc App window.
+  message ArcApp {
+    // The Arc App's ID.
+    optional string app_id = 1;
+
+    // Arc window information.  This maps
+    // to ArcExtraInfo in a WindowInfo struct.
+    optional WindowSize minimum_size = 2;
+    optional WindowSize maximum_size = 3;
+
+    reserved 4;
+
+    optional WindowBound bounds_in_root = 5;
+
+    // maps to gfx::Size.  Width of the window, including the frame,
+    // in pixels.
+    message WindowSize {
+      optional int32 width = 1;
+      optional int32 height = 2;
+    }
+  }
+
+  message WindowBound {
+    // The offset of the window from the top edge of the screen in pixels.
+    optional int32 top = 1;
+    // The offset of the window from the left edge of the screen in pixels.
+    optional int32 left = 2;
+    // The width of the window, including the frame, in pixels.
+    optional int32 width = 3;
+    // The height of the window, including the frame, in pixels.
+    optional int32 height = 4;
+  }
+
+  // Enumeration for the container an app was launched from as used by
+  // (components/services/app_services/public/mojom/types.mojom:490).
+  enum LaunchContainer {
+    LAUNCH_CONTAINER_UNSPECIFIED = 0;
+    LAUNCH_CONTAINER_WINDOW = 1;
+    LAUNCH_CONTAINER_PANEL_DEPRECATED = 2;
+    LAUNCH_CONTAINER_TAB = 3;
+    LAUNCH_CONTAINER_NONE = 4;
+  }
+
+  // The state of a generic window.
+  enum WindowState {
+    UNKNOWN_WINDOW_STATE = 0;
+    // Normal window state (not minimized, maximized, or fullscreen).
+    NORMAL = 1;
+    // Minimized window state.
+    MINIMIZED = 2;
+    // Maximized window state.
+    MAXIMIZED = 3;
+    // Fullscreen window state.
+    FULLSCREEN = 4;
+    // Snapped to primary half of the screen. Primary half is on the left in
+    // landscape screen orientation and top in portrait screen orientation.
+    PRIMARY_SNAPPED = 5;
+    // Snapped to secondary half of the screen. Secondary half is on the right
+    // in landscape screen orientation and bottom in portrait screen
+    // orientation.
+    SECONDARY_SNAPPED = 6;
+    // Floated window state.
+    FLOATED = 7;
+  }
+
+  // Enumeration for how a window opens.  Maps to base::WindowOpenDisposition.
+  // (found in ui/base/window_open_disposition.h:10).  Does not include
+  // MAX_VALUE as MAX_VALUE is equivalent to NEW_PICTURE_IN_PICTURE.  All
+  // comments are copied verbatim from aforementioned header.
+  enum WindowOpenDisposition {
+    UNKNOWN = 0;
+    CURRENT_TAB = 1;
+    // Indicates that only one tab with the URL shoul exist in the same window.
+    SINGLETON_TAB = 2;
+    NEW_FOREGROUND_TAB = 3;
+    NEW_BACKGROUND_TAB = 4;
+    NEW_POPUP = 5;
+    NEW_WINDOW = 6;
+    SAVE_TO_DISK = 7;
+    OFF_THE_RECORD = 8;
+    IGNORE_ACTION = 9;
+    // Activates an existing tab containing the URL, rather than navigating.
+    // This is similar to SINGLETON_TAB, but searches across all windows
+    // from the current profile and anymity (instead of tjust the current one);
+    // closes the current tab on switching if the current ta was the NTP with
+    // no session history; and behaves like CURRENT_TAB instead of
+    // NEW_FOREGROUND_TAB when no existing tab is found.
+    SWITCH_TO_TAB = 10;
+    // creates a new document picture-in-picture window showing a child WebView.
+    NEW_PICTURE_IN_PICTURE = 11;
+  }
+
+  // Enumerates the type of desk, namely to differentiate desks between desks
+  // saved for desk templates and desks saved for save and recall.
+  enum DeskType {
+    UNKNOWN_TYPE = 0;
+    TEMPLATE = 1;
+    SAVE_AND_RECALL = 2;
+    FLOATING_WORKSPACE = 3;
+  }
+
+  // Enumerates the possible colors that a tab group can have.  This mirrors
+  // the enumeration that can be found in
+  // components/tab_groups/tab_group_color.h
+  enum TabGroupColor {
+    UNKNOWN_COLOR = 0;
+    GREY = 1;
+    BLUE = 2;
+    RED = 3;
+    YELLOW = 4;
+    GREEN = 5;
+    PINK = 6;
+    PURPLE = 7;
+    CYAN = 8;
+    ORANGE = 9;
+  }
+
+  // The tab and app entities used by Coral to avoid suggesting groups with a
+  // similar topic.
+  message CoralTabAppEntities {
+    repeated CoralTabEntity tab_entities = 1;
+    repeated CoralAppEntity app_entities = 2;
+  }
+
+  message CoralTabEntity {
+    optional string tab_title = 1;
+    optional string tab_url = 2;
+  }
+
+  message CoralAppEntity {
+    optional string app_name = 1;
+    optional string app_id = 2;
+  }
+}
diff --git a/pyhindsight/lib/content/browser/background_fetch/background_fetch.proto b/pyhindsight/lib/content/browser/background_fetch/background_fetch.proto
new file mode 100644
index 0000000..9baf94a
--- /dev/null
+++ b/pyhindsight/lib/content/browser/background_fetch/background_fetch.proto
@@ -0,0 +1,190 @@
+// Copyright 2017 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content.proto;
+
+// Stores per-registration (as opposed to per-request) data.
+// https://wicg.github.io/background-fetch/#background-fetch-registration
+//
+// Next Tag: 9
+message BackgroundFetchRegistration {
+  enum BackgroundFetchResult {
+    UNSET = 0;  // Default value.
+    FAILURE = 1;
+    SUCCESS = 2;
+  }
+
+  // This should be kept in sync with blink.mojom.BackgroundFetchFailureReason.
+  enum BackgroundFetchFailureReason {
+    NONE = 0;  // Default value.
+    CANCELLED_FROM_UI = 1;
+    CANCELLED_BY_DEVELOPER = 2;
+    BAD_STATUS = 3;
+    FETCH_ERROR = 4;
+    SERVICE_WORKER_UNAVAILABLE = 5;
+    QUOTA_EXCEEDED = 6;
+    DOWNLOAD_TOTAL_EXCEEDED = 7;
+  }
+
+  // See definition of |unique_id| in BackgroundFetchRegistrationId.
+  optional string unique_id = 1;
+
+  // See definition of |developer_id| in BackgroundFetchRegistrationId.
+  optional bytes developer_id = 2;
+
+  optional uint64 upload_total = 3;
+  optional uint64 uploaded = 4;
+  optional uint64 download_total = 5;
+  optional uint64 downloaded = 6;
+  optional BackgroundFetchResult result = 7;
+  optional BackgroundFetchFailureReason failure_reason = 8;
+}
+
+// TODO(crbug.com/40245169): Move ImageResource to generic place.
+// Currently also being used within chrome/browser/web_applications
+// https://w3c.github.io/manifest/#dom-imageresource
+//
+// Next Tag: 5
+message ImageResource {
+  optional string src = 1;
+
+  // Next Tag: 3
+  message Size {
+    optional int32 width = 1;
+    optional int32 height = 2;
+  }
+
+  repeated Size sizes = 2;
+  optional bytes type = 3;
+
+  // https://w3c.github.io/manifest/#purpose-member
+  enum Purpose {
+    ANY = 1;
+    MONOCHROME = 2;
+    MASKABLE = 3;
+  }
+
+  // blink::mojom::ManifestImageResource_Purpose enum.
+  repeated Purpose purpose = 4;
+}
+
+// Developer provided options.
+// https://wicg.github.io/background-fetch/#background-fetch-manager
+//
+// Next Tag: 3
+message BackgroundFetchOptions {
+  // The initial title provided by the developer. This can be updated,
+  // and the most recent value is stored in BackgroundFetchUIOptions.
+  optional string title = 1;
+
+  repeated ImageResource icons = 2;
+
+  optional uint64 download_total = 3;
+}
+
+// Keeps track of the version of the persisted data. If a breaking change
+// needs to be made, increment `CURRENT`, and replace it with a descriptive
+// name of the change. Don't directly check against `SV_CURRENT` as it can be
+// changed.
+// For example, if you want to enable a new key format for the SWDB, perform
+// the following steps:
+// 1. Add a new enum value (SV_ENABLE_NEW_KEY_FORMAT) and increment
+//    `SV_CURRENT`
+// 2. Migrate the old formats on database load (DatabaseMigrationTask).
+// 3. Add a TODO with a bug to clean this up after 2 milestones or so.
+//
+// Next Value: 3
+enum BackgroundFetchStorageVersion {
+  // There was an error when trying to get the storage version.
+  SV_ERROR = -1;
+  // No storage version was found.
+  SV_UNINITIALIZED = 0;
+
+  // Migrate registered fetches to use the new Cache URL key format, to make
+  // them unique, and allow for duplicate requests in a registration.
+  SV_UNIQUE_CACHE_KEYS = 1;
+
+  // Add new versions here.
+
+  // Must be last.
+  SV_CURRENT = 2;
+}
+
+// Stores information about the background fetch that will be persisted
+// to disk. This information should be everything needed to reconstruct
+// the state of an interrupted background fetch.
+//
+// Next Tag: 8
+message BackgroundFetchMetadata {
+  optional int64 creation_microseconds_since_unix_epoch = 1;
+  optional string origin = 2 [deprecated = true];
+
+  optional BackgroundFetchRegistration registration = 3;
+  optional BackgroundFetchOptions options = 4;
+
+  // Number of fetches initiated by the developer.
+  optional int32 num_fetches = 5;
+
+  // Serialized net::IsolationInfo associated with the Background Fetch.
+  optional string isolation_info = 6;
+
+  // Serialized storage key; this replaces origin
+  optional string storage_key = 7;
+}
+
+// All the updateable options that show up in the UI (e.g. notification).
+//
+// Next Tag: 3
+message BackgroundFetchUIOptions {
+  optional string title = 1;
+
+  // Raw bytes needed to deserialize into a PNG icon. Only used if the icon
+  // has a max resolution of 256x256. This means this is at most ~256KB.
+  optional bytes icon = 2;
+}
+
+// A background fetch request that is still in a pending state.
+//
+// Next Tag: 6
+message BackgroundFetchPendingRequest {
+  optional string unique_id = 1;
+  optional int32 request_index = 2;
+  optional string serialized_request = 3;
+  optional uint64 request_body_size = 5;
+
+  reserved 4;
+}
+
+// A background fetch request in the active state. This means that
+// the DownloadManager started downloading the file.
+//
+// Next Tag: 7
+message BackgroundFetchActiveRequest {
+  optional string unique_id = 1;
+  optional int32 request_index = 2;
+  optional string serialized_request = 3;
+  optional string download_guid = 4;
+  optional uint64 request_body_size = 6;
+
+  reserved 5;
+}
+
+// A background fetch request in the completed state. This means that
+// the DownloadManager returned the download.
+//
+// Next Tag: 7
+message BackgroundFetchCompletedRequest {
+  optional string unique_id = 1;
+  optional int32 request_index = 2;
+  optional string serialized_request = 3;
+  optional string download_guid = 4;
+  optional BackgroundFetchRegistration.BackgroundFetchFailureReason
+      failure_reason = 6;
+
+  reserved 5;
+}
diff --git a/pyhindsight/lib/content/browser/background_sync/background_sync.proto b/pyhindsight/lib/content/browser/background_sync/background_sync.proto
new file mode 100644
index 0000000..ec61e02
--- /dev/null
+++ b/pyhindsight/lib/content/browser/background_sync/background_sync.proto
@@ -0,0 +1,38 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content;
+
+enum SyncNetworkState {
+  NETWORK_STATE_ANY = 0;
+  NETWORK_STATE_AVOID_CELLULAR = 1;
+  NETWORK_STATE_ONLINE = 2;
+}
+
+message PeriodicSyncOptions {
+  optional int64 min_interval = 1;
+}
+
+message BackgroundSyncRegistrationProto {
+  // required int64 id = 1;
+  required string tag = 2;
+  // required SyncPeriodicity periodicity = 3;
+  // required int64 min_period = 4;
+  // required SyncNetworkState network_state = 5;
+  // required SyncPowerState power_state = 6;
+  required int32 num_attempts = 7;
+  required int64 delay_until = 8;
+  optional PeriodicSyncOptions periodic_sync_options = 9;
+  optional int32 max_attempts = 10;
+}
+
+message BackgroundSyncRegistrationsProto {
+  repeated BackgroundSyncRegistrationProto registration = 1;
+  // required int64 next_registration_id = 2;
+  required string origin = 3;
+}
\ No newline at end of file
diff --git a/pyhindsight/lib/content/browser/cache_storage/cache_storage.proto b/pyhindsight/lib/content/browser/cache_storage/cache_storage.proto
new file mode 100644
index 0000000..534a534
--- /dev/null
+++ b/pyhindsight/lib/content/browser/cache_storage/cache_storage.proto
@@ -0,0 +1,89 @@
+// Copyright 2014 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content.proto;
+
+message CacheStorageIndex {
+  // The Cache message represents stored caches, where cache names are
+  // preserved as UTF16 strings to align with WebIDL DOMStrings. This ensures
+  // compatibility with names that may contain invalid characters. While the
+  // `name` field remains for backward compatibility, all new caches will use
+  // `u16string_name` going forward. Older clients that read index files written
+  // with UTF8 cache names will not break due to this approach.
+  message Cache {
+    // Maintained for backward compatibility, but no longer used for new caches.
+    required string name = 1;
+    optional string cache_dir = 2;
+    optional int64 size = 3;
+    optional string padding_key = 4 [deprecated = true];
+    optional int64 padding = 5;
+    optional int32 padding_version = 6;
+    optional bytes u16string_name = 7;
+  }
+  repeated Cache cache = 1;
+  optional string origin = 2 [deprecated = true];
+  optional string storage_key = 3;
+  // Note: The bucket ID is cached here for cases where we need it to
+  // build a Cache Storage directory path when a QuotaManagerProxy
+  // is not available, but otherwise it's safer to lookup the bucket
+  // ID using the storage_key since the value stored here might not
+  // always be reliable (for instance, if a crash occurred between the
+  // time that a bucket was deleted and instances had their index files
+  // deleted on disk).
+  optional int64 bucket_id = 4;
+  optional bool bucket_is_default = 5;
+}
+
+message CacheHeaderMap {
+  required string name = 1;
+  required string value = 2;
+}
+
+message CacheRequest {
+  required string method = 1;
+  repeated CacheHeaderMap headers = 2;
+  optional string fragment = 3;
+  optional bool is_reload_navigation = 4;
+  optional bool is_history_navigation = 5;
+}
+
+message CacheResponse {
+  enum ResponseType {
+    BASIC_TYPE = 0;
+    CORS_TYPE = 1;
+    DEFAULT_TYPE = 2;
+    ERROR_TYPE = 3;
+    OPAQUE_TYPE = 4;
+    OPAQUE_REDIRECT_TYPE = 5;
+  }
+
+  required int32 status_code = 1;
+  required string status_text = 2;
+  required ResponseType response_type = 3;
+  repeated CacheHeaderMap headers = 4;
+  optional string url = 5 [deprecated = true];
+  optional int64 response_time = 6;
+  repeated string cors_exposed_header_names = 7;
+  repeated string url_list = 8;
+  optional bool loaded_with_credentials = 9 [deprecated = true];
+  // Mapped to net::HttpResponseInfo::ConnectionInfo via static casting.
+  optional int32 connection_info = 10;
+  optional string alpn_negotiated_protocol = 11;
+  optional bool was_fetched_via_spdy = 12;
+  optional string mime_type = 13;
+  optional string request_method = 14;
+  optional int64 padding = 15;
+  optional int64 side_data_padding = 16;
+  optional bool request_include_credentials = 17;
+}
+
+message CacheMetadata {
+  required CacheRequest request = 1;
+  required CacheResponse response = 2;
+  optional int64 entry_time = 3;
+}
diff --git a/pyhindsight/lib/content/browser/content_index/content_index.proto b/pyhindsight/lib/content/browser/content_index/content_index.proto
new file mode 100644
index 0000000..4f707cf
--- /dev/null
+++ b/pyhindsight/lib/content/browser/content_index/content_index.proto
@@ -0,0 +1,52 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content.proto;
+
+message ContentIconDefinition {
+  optional string src = 1;
+  optional string sizes = 2;
+  optional string type = 3;
+}
+
+// Stores all fields of the developer provided content description.
+message ContentDescription {
+  optional string id = 1;
+  optional string title = 2;
+  optional string description = 3;
+  optional int32 category = 4;
+  repeated ContentIconDefinition icons = 5;
+  optional string launch_url = 6;
+}
+
+// Contains the developer-provided description as well as other metadata that
+// will be useful for ranking content.
+message ContentEntry {
+  optional ContentDescription description = 1;
+
+  // Time from Windows epoch in microseconds.
+  optional int64 timestamp = 2;
+
+  // The complete/resolved URL for the entry. This might differ from
+  // |description.launch_url()| since that field is developer-provided, and
+  // can be an absolute or relative path without the host.
+  optional string launch_url = 3;
+
+  // Whether the ContentIndex entry was created from a top-level context (i.e
+  // not an iframe).
+  optional bool is_top_level_context = 4 [default = true];
+}
+
+// Wrapper to store all the serialized icons.
+message SerializedIcons {
+  // Create a sub-message in case we want to store metadata with the
+  // serialized icon.
+  message SerializedIcon { optional string icon = 1; }
+
+  repeated SerializedIcon icons = 1;
+}
diff --git a/pyhindsight/lib/content/browser/cookie_store/cookie_change_subscriptions.proto b/pyhindsight/lib/content/browser/cookie_store/cookie_change_subscriptions.proto
new file mode 100644
index 0000000..c61da31
--- /dev/null
+++ b/pyhindsight/lib/content/browser/cookie_store/cookie_change_subscriptions.proto
@@ -0,0 +1,27 @@
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto3";
+
+option optimize_for = LITE_RUNTIME;
+
+package content.proto;
+
+// Proto equivalent of network::mojom::CookieMatchType. Values must match.
+enum CookieMatchType {
+  EQUALS = 0;
+  STARTS_WITH = 1;
+}
+
+// A single cookie change subscription.
+message CookieChangeSubscriptionProto {
+  string url = 1;
+  string name = 2;
+  CookieMatchType match_type = 3;
+}
+
+// All cookie change subscriptions belonging to a service worker registration.
+message CookieChangeSubscriptionsProto {
+  repeated CookieChangeSubscriptionProto subscriptions = 1;
+}
diff --git a/pyhindsight/lib/content/browser/devtools/devtools_background_services.proto b/pyhindsight/lib/content/browser/devtools/devtools_background_services.proto
new file mode 100644
index 0000000..ce4ea26
--- /dev/null
+++ b/pyhindsight/lib/content/browser/devtools/devtools_background_services.proto
@@ -0,0 +1,56 @@
+// Copyright 2019 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content.devtools.proto;
+
+// The background service we are logging events for.
+// Do not change the tags since these are persisted.
+// Add a corresponding entry in `enums.xml` if a new value is introduced.
+enum BackgroundService {
+  UNKNOWN = 0;
+  TEST_BACKGROUND_SERVICE = 1;
+  BACKGROUND_FETCH = 2;
+  BACKGROUND_SYNC = 3;
+  PUSH_MESSAGING = 4;
+  NOTIFICATIONS = 5;
+  PAYMENT_HANDLER = 6;
+  PERIODIC_BACKGROUND_SYNC = 7;
+
+  // Keep as last, must have the largest tag value.
+  COUNT = 8;
+}
+
+// A proto for storing the background service event with common metadata for
+// all events.
+//
+// Next Tag: 9
+message BackgroundServiceEvent {
+  // Microseconds since windows epoch.
+  optional int64 timestamp = 1;
+
+  // The origin's URL spec.
+  optional string origin = 2;
+
+  optional int64 service_worker_registration_id = 3;
+
+  optional BackgroundService background_service = 4;
+
+  // A descriptive name for the event that is being logged.
+  optional string event_name = 5;
+
+  // The instance this event belongs to. This is for grouping related events.
+  // For example for Background Fetch and Background Sync, this would be the
+  // developer provided ID to create the fetch/sync.
+  optional string instance_id = 6;
+
+  // Additional custom information related to this event.
+  map<string, string> event_metadata = 7;
+
+  // Storage key the background service belongs to.
+  optional string storage_key = 8;
+}
diff --git a/pyhindsight/lib/content/browser/download/embedder_download_data.proto b/pyhindsight/lib/content/browser/download/embedder_download_data.proto
new file mode 100644
index 0000000..a6f7634
--- /dev/null
+++ b/pyhindsight/lib/content/browser/download/embedder_download_data.proto
@@ -0,0 +1,30 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+option optimize_for = LITE_RUNTIME;
+
+package content.proto;
+
+// EmbedderDownloadData contains data that is stored in the download history
+// database.
+message EmbedderDownloadData {
+  optional StoragePartitionConfig storage_partition_config = 1;
+}
+
+// StoragePartitionConfig stores data from the content::StoragePartitionConfig
+// class. It enables this data to be serialized for storage in the download
+// history database.
+message StoragePartitionConfig {
+  enum FallbackMode {
+    kNone = 0;
+    kPartitionOnDisk = 1;
+    kPartitionInMemory = 2;
+  }
+
+  required string partition_domain = 1;
+  required string partition_name = 2;
+  required bool in_memory = 3;
+  required FallbackMode fallback_mode = 4;
+}
diff --git a/pyhindsight/lib/content/browser/notifications/notification_database_data.proto b/pyhindsight/lib/content/browser/notifications/notification_database_data.proto
new file mode 100644
index 0000000..c284eed
--- /dev/null
+++ b/pyhindsight/lib/content/browser/notifications/notification_database_data.proto
@@ -0,0 +1,98 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content;
+
+// Stores information about a Web Notification. This message is the protocol
+// buffer meant to serialize the content::NotificationDatabaseData structure.
+//
+// Next tag: 17
+message NotificationDatabaseDataProto {
+  enum ClosedReason {
+    USER = 0;
+    DEVELOPER = 1;
+    UNKNOWN = 2;
+  }
+
+  // DEPRECATED: Use |notification_id| instead.
+  optional int64 persistent_notification_id = 1;
+
+  optional string notification_id = 5;
+
+  optional string origin = 2;
+  optional int64 service_worker_registration_id = 3;
+  optional bool replaced_existing_notification = 6;
+  optional int32 num_clicks = 7;
+  optional int32 num_action_button_clicks = 8;
+  optional int64 creation_time_millis = 9;
+  optional int64 time_until_first_click_millis = 10;
+  optional int64 time_until_last_click_millis = 11;
+  optional int64 time_until_close_millis = 12;
+  optional ClosedReason closed_reason = 13;
+
+  // A notification action, corresponds to blink::PlatformNotificationAction.
+  //
+  // Next tag: 6
+  message NotificationAction {
+    // Corresponds to blink::mojom::NotificationActionType.
+    enum Type {
+      BUTTON = 0;
+      TEXT = 1;
+    }
+
+    optional string action = 1;
+    optional string title = 2;
+    optional string icon = 3;
+    optional Type type = 4;
+    optional string placeholder = 5;
+  }
+
+  // Actual data payload of the notification. This message is the protocol
+  // buffer meant to serialize the blink::PlatformNotificationData structure.
+  //
+  // Next tag: 17
+  message NotificationData {
+    enum Direction {
+      LEFT_TO_RIGHT = 0;
+      RIGHT_TO_LEFT = 1;
+      AUTO = 2;
+    }
+
+    optional string title = 1;
+    optional Direction direction = 2;
+    optional string lang = 3;
+    optional string body = 4;
+    optional string tag = 5;
+    optional string image = 15;
+    optional string icon = 6;
+    optional string badge = 14;
+    repeated int32 vibration_pattern = 9 [packed=true];
+    optional int64 timestamp = 12;
+    optional bool renotify = 13;
+    optional bool silent = 7;
+    optional bool require_interaction = 11;
+    optional bytes data = 8;
+    repeated NotificationAction actions = 10;
+    // Stored as offset from the windows epoch in microseconds.
+    optional int64 show_trigger_timestamp = 16;
+  }
+
+  optional NotificationData notification_data = 4;
+
+  // Keeps track if a notification with a |show_trigger_timestamp| has been
+  // displayed already.
+  optional bool has_triggered = 14;
+
+  // Flag for notifications shown by the browser that should not be visible to
+  // the origin when requesting a list of notifications.
+  optional bool is_shown_by_browser = 15;
+
+  // Notification metadata map, where the key is the type of metadata and the
+  // value is any string value of data, such as a serialized dictionary.
+  map<string, string> serialized_metadata = 16;
+}
diff --git a/pyhindsight/lib/content/browser/payments/payment_app.proto b/pyhindsight/lib/content/browser/payments/payment_app.proto
new file mode 100644
index 0000000..a2939cd
--- /dev/null
+++ b/pyhindsight/lib/content/browser/payments/payment_app.proto
@@ -0,0 +1,59 @@
+// Copyright 2016 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+syntax = "proto2";
+
+option optimize_for = LITE_RUNTIME;
+
+package content;
+
+message StoredPaymentInstrumentKeyInfoProto {
+  optional uint64 insertion_order = 1;
+  optional string key = 2;
+}
+
+message ImageSizeProto {
+  optional uint64 width = 1;
+  optional uint64 height = 2;
+}
+
+message StoredPaymentInstrumentImageObject {
+  optional string src = 1;
+  optional string type = 2;
+  repeated ImageSizeProto sizes = 3;
+}
+
+message StoredPaymentInstrumentProto {
+  optional int64 registration_id = 1;
+  optional string instrument_key = 2;
+  optional string name = 3;
+  optional string method = 4;
+  optional string stringified_capabilities = 5;
+  repeated StoredPaymentInstrumentImageObject icons = 6;
+  optional string decoded_instrument_icon = 7;
+  repeated int32 supported_card_networks = 8;
+}
+
+message StoredRelatedApplicationProto {
+  optional string platform = 1;
+  optional string id = 2;
+}
+
+message SupportedDelegationsProto {
+  optional bool shipping_address = 1;
+  optional bool payer_name = 2;
+  optional bool payer_phone = 3;
+  optional bool payer_email = 4;
+}
+
+message StoredPaymentAppProto {
+  optional int64 registration_id = 1;
+  optional string scope = 2;
+  optional string name = 3;
+  optional string icon = 4;
+  optional bool prefer_related_applications = 5;
+  repeated StoredRelatedApplicationProto related_applications = 6;
+  optional string user_hint = 7;
+  optional SupportedDelegationsProto supported_delegations = 8;
+}