PostHog · adboio · Jul 17, 2026
diff --git a/packages/ui/src/features/message-editor/tiptap/MentionChipNode.ts b/packages/ui/src/features/message-editor/tiptap/MentionChipNode.ts
@@ -27,6 +27,11 @@ export interface MentionChipAttrs {
   skillName?: string;
 }
 
+export interface MentionChipOptions {
+  getPastedText: (chipId: string) => string | null;
+  forgetPastedText: (chipId: string) => void;
+}
+
 declare module "@tiptap/core" {
   interface Commands<ReturnType> {
     mentionChip: {
@@ -40,13 +45,20 @@ declare module "@tiptap/core" {
   }
 }
 
-export const MentionChipNode = Node.create({
+export const MentionChipNode = Node.create<MentionChipOptions>({
   name: "mentionChip",
   group: "inline",
   inline: true,
   selectable: true,
   atom: true,
 
+  addOptions() {
+    return {
+      getPastedText: () => null,
+      forgetPastedText: () => {},
+    };
+  },
+
   addAttributes() {
     return {
       type: { default: "file" as ChipType },

diff --git a/packages/ui/src/features/message-editor/tiptap/MentionChipView.test.tsx b/packages/ui/src/features/message-editor/tiptap/MentionChipView.test.tsx
@@ -0,0 +1,92 @@
+import { fireEvent, render, screen } from "@testing-library/react";
+import type { NodeViewProps } from "@tiptap/react";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { usePasteUndoStore } from "../pasteUndoStore";
+import { MentionChipView } from "./MentionChipView";
+
+vi.mock("@posthog/quill", () => ({
+  Chip: ({
+    children,
+    onClick,
+  }: React.PropsWithChildren<{ onClick?: () => void }>) => (
+    <>
+      {children}
+      <button type="button" onClick={onClick}>
+        Expand pasted text
+      </button>
+    </>
+  ),
+}));
+
+vi.mock("@posthog/ui/primitives/Tooltip", () => ({
+  Tooltip: ({ children }: React.PropsWithChildren) => children,
+}));
+
+vi.mock("@tiptap/react", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@tiptap/react")>();
+  return {
+    ...actual,
+    NodeViewWrapper: ({ children }: React.PropsWithChildren) => (
+      <span>{children}</span>
+    ),
+  };
+});
+
+describe("MentionChipView", () => {
+  beforeEach(() => {
+    usePasteUndoStore.getState().setUndoableChipId(null);
+  });
+
+  it("expands pasted text when the chip is clicked", () => {
+    const content = "first line\nsecond line";
+    const forgetPastedText = vi.fn();
+    const insertText = vi.fn();
+    const chain = {
+      focus: vi.fn(),
+      command: vi.fn(),
+      run: vi.fn(),
+    };
+    chain.focus.mockReturnValue(chain);
+    chain.command.mockImplementation(
+      (
+        callback: (props: { tr: { insertText: typeof insertText } }) => boolean,
+      ) => {
+        callback({ tr: { insertText } });
+        return chain;
+      },
+    );
+    chain.run.mockReturnValue(true);
+
+    render(
+      <MentionChipView
+        {...({
+          node: {
+            attrs: {
+              type: "file",
+              id: "/tmp/pasted.txt",
+              label: "Pasted text #1 (2 lines)",
+              pastedText: true,
+              chipId: "paste-1",
+            },
+            nodeSize: 1,
+          },
+          getPos: () => 4,
+          editor: { chain: () => chain },
+          extension: {
+            options: {
+              getPastedText: () => content,
+              forgetPastedText,
+            },
+          },
+          selected: false,
+        } as unknown as NodeViewProps)}
+      />,
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: "Expand pasted text" }));
+
+    expect(insertText).toHaveBeenCalledWith(content, 4, 5);
+    expect(chain.run).toHaveBeenCalled();
+    expect(forgetPastedText).toHaveBeenCalledWith("paste-1");
+  });
+});
diff --git a/packages/ui/src/features/message-editor/tiptap/MentionChipView.tsx b/packages/ui/src/features/message-editor/tiptap/MentionChipView.tsx
@@ -11,10 +11,15 @@ import {
   XIcon,
 } from "@phosphor-icons/react";
 import { Chip } from "@posthog/quill";
+import { useSettingsStore as useFeatureSettingsStore } from "@posthog/ui/features/settings/settingsStore";
 import { Tooltip } from "@posthog/ui/primitives/Tooltip";
 import { type NodeViewProps, NodeViewWrapper } from "@tiptap/react";
 import { usePasteUndoStore } from "../pasteUndoStore";
-import type { ChipType, MentionChipAttrs } from "./MentionChipNode";
+import type {
+  ChipType,
+  MentionChipAttrs,
+  MentionChipOptions,
+} from "./MentionChipNode";
 
 const chipBase = "group/chip relative top-px active:translate-y-0 pl-1";
 
@@ -67,16 +72,20 @@ function DefaultChip({
   label,
   chipId,
   pastedText,
+  canExpandPastedText,
   selected,
   onRemove,
+  onExpandPastedText,
 }: {
   type: string;
   id: string;
   label: string;
   chipId: string | null;
   pastedText: boolean;
+  canExpandPastedText: boolean;
   selected: boolean;
   onRemove: () => void;
+  onExpandPastedText: () => void;
 }) {
   const undoableChipId = usePasteUndoStore((state) => state.undoableChipId);
   const canUndoPaste =
@@ -87,13 +96,20 @@ function DefaultChip({
   const isFolder = type === "folder";
   const isGithubRef = type === "github_issue" || type === "github_pr";
   const canOpenUrl = isGithubRef && /^https:\/\//.test(id);
+  const isClickable = canOpenUrl || canExpandPastedText;
 
   const chipContent = (
     <Chip
       size="xs"
       contentEditable={false}
-      onClick={canOpenUrl ? () => window.open(id, "_blank") : undefined}
-      className={`${chipBase} max-w-full whitespace-nowrap ${isGithubRef ? "cursor-pointer!" : "cursor-default! active:translate-y-0!"} ${isCommand ? "cli-slash-command" : "cli-file-mention"} ${selected ? selectedRing : ""}`}
+      onClick={
+        canOpenUrl
+          ? () => window.open(id, "_blank")
+          : canExpandPastedText
+            ? onExpandPastedText
+            : undefined
+      }
+      className={`${chipBase} max-w-full whitespace-nowrap ${isClickable ? "cursor-pointer!" : "cursor-default! active:translate-y-0!"} ${isCommand ? "cli-slash-command" : "cli-file-mention"} ${selected ? selectedRing : ""}`}
     >
       <IconCloseButton type={type as ChipType} onRemove={onRemove} />
       {isGithubRef ? (
@@ -105,11 +121,12 @@ function DefaultChip({
   );
 
   if (isFile || isFolder) {
-    return (
-      <Tooltip content={canUndoPaste ? "Paste again to expand as text" : id}>
-        {chipContent}
-      </Tooltip>
-    );
+    const tooltip = canExpandPastedText
+      ? canUndoPaste
+        ? "Click or paste again to expand as text"
+        : "Click to expand as text"
+      : id;
+    return <Tooltip content={tooltip}>{chipContent}</Tooltip>;
   }
 
   return chipContent;
@@ -119,10 +136,15 @@ export function MentionChipView({
   node,
   getPos,
   editor,
+  extension,
   selected,
 }: NodeViewProps) {
   const { type, id, label, pastedText, chipId } =
     node.attrs as MentionChipAttrs;
+  const { getPastedText, forgetPastedText } =
+    extension.options as MentionChipOptions;
+  const canExpandPastedText =
+    pastedText && chipId != null && getPastedText(chipId) !== null;
 
   const handleRemove = () => {
     const pos = getPos();
@@ -132,6 +154,28 @@ export function MentionChipView({
       .focus()
       .deleteRange({ from: pos, to: pos + node.nodeSize })
       .run();
+    if (chipId) forgetPastedText(chipId);
+  };
+
+  const handleExpandPastedText = () => {
+    if (!chipId) return;
+    const content = getPastedText(chipId);
+    if (content === null) return;
+
+    const pos = getPos();
+    if (pos == null) return;
+
+    editor
+      .chain()
+      .focus()
+      .command(({ tr }) => {
+        tr.insertText(content, pos, pos + node.nodeSize);
+        return true;
+      })
+      .run();
+    forgetPastedText(chipId);
+    usePasteUndoStore.getState().setUndoableChipId(null);
+    useFeatureSettingsStore.getState().markHintLearned("paste-as-file");
   };
 
   return (
@@ -142,8 +186,10 @@ export function MentionChipView({
         label={label}
         chipId={chipId ?? null}
         pastedText={pastedText}
+        canExpandPastedText={canExpandPastedText}
         selected={selected}
         onRemove={handleRemove}
+        onExpandPastedText={handleExpandPastedText}
       />
     </NodeViewWrapper>
   );

diff --git a/packages/ui/src/features/message-editor/tiptap/extensions.ts b/packages/ui/src/features/message-editor/tiptap/extensions.ts
@@ -1,16 +1,19 @@
+import type { AnyExtension } from "@tiptap/core";
 import Placeholder from "@tiptap/extension-placeholder";
 import StarterKit from "@tiptap/starter-kit";
 import { createCommandMention } from "./CommandMention";
 import { createFileMention } from "./FileMention";
 import { createIssueMention } from "./IssueMention";
-import { MentionChipNode } from "./MentionChipNode";
+import { MentionChipNode, type MentionChipOptions } from "./MentionChipNode";
 
 export interface EditorExtensionsOptions {
   sessionId: string;
   placeholder?: string;
   fileMentions?: boolean;
   issueMentions?: boolean;
   commands?: boolean;
+  getPastedText?: MentionChipOptions["getPastedText"];
+  forgetPastedText?: MentionChipOptions["forgetPastedText"];
 }
 
 export function getEditorExtensions(options: EditorExtensionsOptions) {
@@ -20,9 +23,11 @@ export function getEditorExtensions(options: EditorExtensionsOptions) {
     fileMentions = true,
     issueMentions = true,
     commands = true,
+    getPastedText = () => null,
+    forgetPastedText = () => {},
   } = options;
 
-  const extensions = [
+  const extensions: AnyExtension[] = [
     StarterKit.configure({
       heading: false,
       blockquote: false,
@@ -37,7 +42,7 @@ export function getEditorExtensions(options: EditorExtensionsOptions) {
       code: false,
     }),
     Placeholder.configure({ placeholder }),
-    MentionChipNode,
+    MentionChipNode.configure({ getPastedText, forgetPastedText }),
   ];
 
   if (fileMentions) {

diff --git a/packages/ui/src/features/message-editor/tiptap/useTiptapEditor.ts b/packages/ui/src/features/message-editor/tiptap/useTiptapEditor.ts
@@ -114,11 +114,13 @@ async function pasteTextAsFile(
   text: string,
   pasteCountRef: React.MutableRefObject<number>,
   tracked?: TrackedAutoConvertedPaste,
+  rememberPastedText?: (chipId: string, text: string) => void,
 ): Promise<void> {
   const result = await persistTextContent(text);
   if (tracked?.status === "canceled") return;
   pasteCountRef.current += 1;
   const lineCount = text.split("\n").length;
+  if (tracked) rememberPastedText?.(tracked.chipId, text);
   insertChipWithTrailingSpace(view, {
     type: "file",
     id: result.path,
@@ -319,6 +321,7 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
   const lastAutoConvertedPasteRef = useRef<TrackedAutoConvertedPaste | null>(
     null,
   );
+  const pastedTextByChipIdRef = useRef(new Map<string, string>());
   useEffect(() => {
     return () => {
       if (lastAutoConvertedPasteRef.current) {
@@ -339,6 +342,11 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
         placeholder,
         fileMentions,
         commands,
+        getPastedText: (chipId) =>
+          pastedTextByChipIdRef.current.get(chipId) ?? null,
+        forgetPastedText: (chipId) => {
+          pastedTextByChipIdRef.current.delete(chipId);
+        },
       }),
       editable: !disabled,
       autofocus: autoFocus ? "end" : false,
@@ -368,7 +376,24 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
                 useFeatureSettingsStore
                   .getState()
                   .markHintLearned("paste-inline");
-                await pasteTextAsFile(view, text, pasteCountRef);
+                const tracked: TrackedAutoConvertedPaste = {
+                  clipboardText: text,
+                  insertText: text,
+                  chipId: crypto.randomUUID(),
+                  kind: "file",
+                  status: "pending",
+                };
+                lastAutoConvertedPasteRef.current = tracked;
+                usePasteUndoStore.getState().setUndoableChipId(tracked.chipId);
+                await pasteTextAsFile(
+                  view,
+                  text,
+                  pasteCountRef,
+                  tracked,
+                  (chipId, pastedText) => {
+                    pastedTextByChipIdRef.current.set(chipId, pastedText);
+                  },
+                );
               } catch (_error) {
                 toast.error("Failed to paste as file attachment");
               }
@@ -549,6 +574,7 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
               )
             ) {
               event.preventDefault();
+              pastedTextByChipIdRef.current.delete(lastConverted.chipId);
               if (lastConverted.kind === "file") {
                 useFeatureSettingsStore
                   .getState()
@@ -652,6 +678,9 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
                   effectiveText,
                   pasteCountRef,
                   tracked,
+                  (chipId, text) => {
+                    pastedTextByChipIdRef.current.set(chipId, text);
+                  },
                 );
                 if (tracked.status !== "canceled") {
                   showPasteHint(
@@ -780,6 +809,7 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
       editor.commands.clearContent();
       prevBashModeRef.current = false;
       pasteCountRef.current = 0;
+      pastedTextByChipIdRef.current.clear();
       setAttachments([]);
       draft.clearDraft();
     };
@@ -832,6 +862,7 @@ export function useTiptapEditor(options: UseTiptapEditorOptions) {
   const clear = useCallback(() => {
     editor?.commands.clearContent();
     prevBashModeRef.current = false;
+    pastedTextByChipIdRef.current.clear();
     setAttachments([]);
     draft.clearDraft();
   }, [editor, draft]);