diff --git a/.gitignore b/.gitignore
index 74124a748..11912c418 100644
--- a/.gitignore
+++ b/.gitignore
@@ -103,3 +103,5 @@ ENV/
 *~
 
 /uv.lock
+
+/.codex
diff --git a/default_countries.csv b/default_countries.csv
index a8a4a6545..788811c39 100644
--- a/default_countries.csv
+++ b/default_countries.csv
@@ -1,5 +1,6 @@
 code
 af_za
+agr_pe
 am_et
 ar_aa
 as_in
@@ -33,6 +34,7 @@ gu_in
 gv_gb
 he_il
 hi_in
+hif_fj
 hr_hr
 hu_hu
 hy_am
@@ -55,6 +57,7 @@ lo_la
 lt_lt
 lv_lv
 mi_nz
+miq_ni
 mk_mk
 ml_in
 mn_mn
@@ -63,6 +66,7 @@ ms_my
 mt_mt
 my_mm
 ne_np
+nhn_mx
 nl_nl
 nn_no
 no_no
@@ -82,6 +86,7 @@ rw_rw
 sa_in
 sd_in
 si_lk
+shs_ca
 sk_sk
 sl_si
 sq_al
@@ -93,6 +98,7 @@ ta_in
 te_in
 tg_tj
 th_th
+the_np
 tk_tm
 tl_ph
 tn_za
@@ -100,6 +106,7 @@ tr_tr
 ts_za
 tt_ru
 uk_ua
+unm_us
 ur_pk
 uz_uz
 ve_za
@@ -107,6 +114,7 @@ vi_vn
 wa_be
 xh_za
 yi_us
+yuw_pg
 zu_za
 ast_es
 gug_py
diff --git a/languages.csv b/languages.csv
index e2105fda8..8948d0ff8 100644
--- a/languages.csv
+++ b/languages.csv
@@ -12,6 +12,7 @@ af,Afrikaans,2,n != 1
 afh,Afrihili,2,n != 1
 aii,Assyrian Neo-Aramaic,2,n != 1
 ain,Ainu (Japan),2,n != 1
+agr,Aguaruna,2,n != 1
 ak,Akan,2,n > 1
 akk,Akkadian,2,n != 1
 ale,Aleut,2,n != 1
@@ -300,6 +301,7 @@ he_IL,Hebrew (Israel),4,(n == 1) ? 0 : ((n == 2) ? 1 : ((n > 10 && n % 10 == 0)
 hi,Hindi,2,n > 1
 hi@hinglish,Hindi (Hinglish),2,n > 1
 hi_Latn,Hindi (Latin script),2,n > 1
+hif,Hindi (Fiji),2,n != 1
 hil,Hiligaynon,2,n != 1
 hit,Hittite,2,n != 1
 hmn,Hmong,2,n != 1
@@ -459,6 +461,7 @@ mi,Maori,2,n > 1
 mia,Miami,2,n > 1
 mic,Mi'kmaq,2,n != 1
 min,Minangkabau,2,n != 1
+miq,Mískito,2,n != 1
 mis,Milang,1,0
 mjw,Karbi,2,n != 1
 mk,Macedonian,2,n==1 || n%10==1 ? 0 : 1
@@ -510,6 +513,7 @@ ne,Nepali,2,n != 1
 new,Newari,2,n != 1
 ng,Ndonga,2,n != 1
 ngl,Lomwe,2,n != 1
+nhn,Nahuatl (Central),2,n != 1
 nia,Nias,2,n != 1
 nij,Ngaju,2,n != 1
 niu,Niuean,2,n != 1
@@ -648,6 +652,7 @@ smj,Sami (Lule),3,(n == 1) ? 0 : ((n == 2) ? 1 : 2)
 sml,Sama (Central),2,n != 1
 smn,Sami (Inari),3,(n == 1) ? 0 : ((n == 2) ? 1 : 2)
 sms,Sami (Skolt),3,(n == 1) ? 0 : ((n == 2) ? 1 : 2)
+shs,Shuswap,2,n != 1
 sn,Shona,2,n != 1
 snk,Soninke,2,n != 1
 so,Somali,2,n != 1
@@ -710,6 +715,7 @@ tog,Tonga (Nyasa),2,n != 1
 toi,Tonga (Zambia),2,n != 1
 tok,Toki Pona,1,0
 tpi,Tok Pisin,1,0
+the,Tharu (Chitwania),2,n != 1
 tr,Turkish,2,n != 1
 trv,Taroko,2,n != 1
 ts,Tsonga,2,n != 1
@@ -733,6 +739,7 @@ uga,Ugaritic,2,n != 1
 uk,Ukrainian,3,n%10==1 && n%100!=11 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2
 umb,Umbundu,2,n != 1
 und,Undetermined,2,n != 1
+unm,Unami,2,n != 1
 unr,Mundari,2,n != 1
 ur,Urdu,2,n != 1
 ur_IN,Urdu (India),2,n != 1
@@ -770,6 +777,7 @@ xog,Soga,2,n != 1
 yao,Yao,2,n != 1
 yap,Yapese,2,n != 1
 yi,Yiddish,2,n != 1
+yuw,Yau (Morobe Province),2,n != 1
 yo,Yoruba,1,0
 yua,Yucateco,2,n != 1
 yue_Hans,Cantonese (Simplified Han script),1,0
diff --git a/scripts/lint.py b/scripts/lint.py
index 2cfeed494..9b07e2066 100755
--- a/scripts/lint.py
+++ b/scripts/lint.py
@@ -5,6 +5,7 @@
 # SPDX-License-Identifier: MIT
 
 import csv
+import os
 from gettext import c2py
 from itertools import chain
 
@@ -23,6 +24,59 @@ def parse_csv(name):
     return result
 
 
+def normalize_supported_locale(locale):
+    return locale.split(".", 1)[0].lower()
+
+
+def is_supported_locale(locale, languages, aliases, default_countries):
+    candidates = [locale]
+    normalized = locale
+
+    if "@" in normalized:
+        base, modifier = normalized.split("@", 1)
+        if modifier == "euro":
+            candidates.append(base)
+            normalized = base
+        else:
+            language = base.split("_", 1)[0]
+            candidates.extend((f"{language}@{modifier}", base))
+            normalized = base
+
+    if "_" in normalized:
+        language = normalized.split("_", 1)[0]
+        candidates.append(language)
+        if normalized in default_countries:
+            candidates.append(language)
+
+    return any(
+        candidate in languages or candidate in aliases for candidate in candidates
+    )
+
+
+def validate_supported_locales(languages, aliases, default_countries):
+    supported_path = "/usr/share/i18n/SUPPORTED"
+    if not os.path.exists(supported_path):
+        return
+
+    missing = set()
+
+    with open(supported_path) as handle:
+        for line in handle:
+            if not line.strip():
+                continue
+            locale = normalize_supported_locale(line.split()[0])
+            if locale in {"c", "posix"}:
+                continue
+            if not is_supported_locale(locale, languages, aliases, default_countries):
+                missing.add(locale)
+
+    if missing:
+        raise ValueError(
+            "Missing locales from /usr/share/i18n/SUPPORTED: "
+            + ", ".join(sorted(missing))
+        )
+
+
 languages = parse_csv("languages.csv")
 aliases = parse_csv("aliases.csv")
 cldr = parse_csv("cldr.csv")
@@ -80,3 +134,7 @@ def parse_csv(name):
         raise ValueError(
             f"Mismatching plural count for {code}: {plural_count} != {calculated}",
         )
+
+validate_supported_locales(
+    set(languages.keys()), aliases, set(default_countries.keys())
+)
diff --git a/weblate_language_data/countries.py b/weblate_language_data/countries.py
index 1c473645c..e322a3e63 100644
--- a/weblate_language_data/countries.py
+++ b/weblate_language_data/countries.py
@@ -15,6 +15,7 @@
 # List of default languages, omitting country code should be okay
 DEFAULT_LANGS: tuple[str, ...] = (
     "af_za",
+    "agr_pe",
     "am_et",
     "ar_aa",
     "as_in",
@@ -48,6 +49,7 @@
     "gv_gb",
     "he_il",
     "hi_in",
+    "hif_fj",
     "hr_hr",
     "hu_hu",
     "hy_am",
@@ -70,6 +72,7 @@
     "lt_lt",
     "lv_lv",
     "mi_nz",
+    "miq_ni",
     "mk_mk",
     "ml_in",
     "mn_mn",
@@ -78,6 +81,7 @@
     "mt_mt",
     "my_mm",
     "ne_np",
+    "nhn_mx",
     "nl_nl",
     "nn_no",
     "no_no",
@@ -97,6 +101,7 @@
     "sa_in",
     "sd_in",
     "si_lk",
+    "shs_ca",
     "sk_sk",
     "sl_si",
     "sq_al",
@@ -108,6 +113,7 @@
     "te_in",
     "tg_tj",
     "th_th",
+    "the_np",
     "tk_tm",
     "tl_ph",
     "tn_za",
@@ -115,6 +121,7 @@
     "ts_za",
     "tt_ru",
     "uk_ua",
+    "unm_us",
     "ur_pk",
     "uz_uz",
     "ve_za",
@@ -122,6 +129,7 @@
     "wa_be",
     "xh_za",
     "yi_us",
+    "yuw_pg",
     "zu_za",
     "ast_es",
     "gug_py",
diff --git a/weblate_language_data/language_codes.py b/weblate_language_data/language_codes.py
index ed7843bc9..f67de15b1 100644
--- a/weblate_language_data/language_codes.py
+++ b/weblate_language_data/language_codes.py
@@ -29,6 +29,7 @@
     "af",
     "afh",
     "afr",
+    "agr",
     "aii",
     "ain",
     "ais",
@@ -494,6 +495,7 @@
     "hi",
     "hi@hinglish",
     "hi_latn",
+    "hif",
     "hil",
     "hin",
     "hit",
@@ -735,6 +737,7 @@
     "mia",
     "mic",
     "min",
+    "miq",
     "mis",
     "mjw",
     "mk",
@@ -810,6 +813,7 @@
     "new",
     "ng",
     "ngl",
+    "nhn",
     "nia",
     "nij",
     "niu",
@@ -1000,6 +1004,7 @@
     "sh",
     "shi",
     "shn",
+    "shs",
     "si",
     "sid",
     "sin",
@@ -1107,6 +1112,7 @@
     "tgl",
     "th",
     "tha",
+    "the",
     "ti",
     "tib",
     "tig",
@@ -1165,6 +1171,7 @@
     "umb",
     "umu",
     "und",
+    "unm",
     "unr",
     "ur",
     "ur_in",
@@ -1232,6 +1239,7 @@
     "yue",
     "yue_hans",
     "yue_hant",
+    "yuw",
     "za",
     "zai",
     "zap",
diff --git a/weblate_language_data/languages.py b/weblate_language_data/languages.py
index d126ba4af..8773a0bdc 100644
--- a/weblate_language_data/languages.py
+++ b/weblate_language_data/languages.py
@@ -133,6 +133,15 @@
         2,
         "n != 1",
     ),
+    (
+        "agr",
+        # Translators: Language name for ISO code "agr". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Aguaruna"),
+        2,
+        "n != 1",
+    ),
     (
         "ak",
         # Translators: Language name for ISO code "ak". The parenthesis clarifies
@@ -2725,6 +2734,15 @@
         2,
         "n > 1",
     ),
+    (
+        "hif",
+        # Translators: Language name for ISO code "hif". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Hindi (Fiji)"),
+        2,
+        "n != 1",
+    ),
     (
         "hil",
         # Translators: Language name for ISO code "hil". The parenthesis clarifies
@@ -4156,6 +4174,15 @@
         2,
         "n != 1",
     ),
+    (
+        "miq",
+        # Translators: Language name for ISO code "miq". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Mískito"),
+        2,
+        "n != 1",
+    ),
     (
         "mis",
         # Translators: Language name for ISO code "mis". The parenthesis clarifies
@@ -4615,6 +4642,15 @@
         2,
         "n != 1",
     ),
+    (
+        "nhn",
+        # Translators: Language name for ISO code "nhn". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Nahuatl (Central)"),
+        2,
+        "n != 1",
+    ),
     (
         "nia",
         # Translators: Language name for ISO code "nia". The parenthesis clarifies
@@ -5857,6 +5893,15 @@
         3,
         "(n == 1) ? 0 : ((n == 2) ? 1 : 2)",
     ),
+    (
+        "shs",
+        # Translators: Language name for ISO code "shs". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Shuswap"),
+        2,
+        "n != 1",
+    ),
     (
         "sn",
         # Translators: Language name for ISO code "sn". The parenthesis clarifies
@@ -6415,6 +6460,15 @@
         1,
         "0",
     ),
+    (
+        "the",
+        # Translators: Language name for ISO code "the". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Tharu (Chitwania)"),
+        2,
+        "n != 1",
+    ),
     (
         "tr",
         # Translators: Language name for ISO code "tr". The parenthesis clarifies
@@ -6622,6 +6676,15 @@
         2,
         "n != 1",
     ),
+    (
+        "unm",
+        # Translators: Language name for ISO code "unm". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Unami"),
+        2,
+        "n != 1",
+    ),
     (
         "unr",
         # Translators: Language name for ISO code "unr". The parenthesis clarifies
@@ -6955,6 +7018,15 @@
         2,
         "n != 1",
     ),
+    (
+        "yuw",
+        # Translators: Language name for ISO code "yuw". The parenthesis clarifies
+        # variant of the language. It could contain a region, age (Old, Middle, ...)
+        # or other variant.
+        _("Yau (Morobe Province)"),
+        2,
+        "n != 1",
+    ),
     (
         "yo",
         # Translators: Language name for ISO code "yo". The parenthesis clarifies
diff --git a/weblate_language_data/population.py b/weblate_language_data/population.py
index 9a5ba5dcd..938bc432e 100644
--- a/weblate_language_data/population.py
+++ b/weblate_language_data/population.py
@@ -27,6 +27,7 @@
     "afh": 0,
     "aii": 0,
     "ain": 0,
+    "agr": 0,
     "ak": 13489749,
     "akk": 0,
     "ale": 0,
@@ -315,6 +316,7 @@
     "hi": 580318483,
     "hi@hinglish": 580318483,
     "hi_Latn": 1409130,
+    "hif": 390160,
     "hil": 9935268,
     "hit": 0,
     "hmn": 0,
@@ -474,6 +476,7 @@
     "mia": 0,
     "mic": 9310,
     "min": 8446860,
+    "miq": 0,
     "mis": 0,
     "mjw": 0,
     "mk": 1612846,
@@ -525,6 +528,7 @@
     "new": 1027039,
     "ng": 588768,
     "ngl": 2267868,
+    "nhn": 0,
     "nia": 0,
     "nij": 1041779,
     "niu": 1120,
@@ -663,6 +667,7 @@
     "sml": 0,
     "smn": 618,
     "sms": 618,
+    "shs": 0,
     "sn": 13891824,
     "snk": 1297445,
     "so": 18630626,
@@ -725,6 +730,7 @@
     "toi": 2287901,
     "tok": 0,
     "tpi": 7132802,
+    "the": 0,
     "tr": 82419542,
     "trv": 4719,
     "ts": 5313550,
@@ -748,6 +754,7 @@
     "uk": 24080585,
     "umb": 10788609,
     "und": 302,
+    "unm": 0,
     "unr": 1324582,
     "ur": 313093257,
     "ur_IN": 70456500,
@@ -785,6 +792,7 @@
     "yao": 800424,
     "yap": 6573,
     "yi": 916209,
+    "yuw": 0,
     "yo": 31761815,
     "yua": 875958,
     "yue_Hans": 73634080,