From 2140729a54eda0304be59f3f4f51e7ca298fea8b Mon Sep 17 00:00:00 2001
From: Shahryar Tayeb <48182832+shtayeb@users.noreply.github.com>
Date: Sat, 4 Apr 2026 04:01:39 +0900
Subject: [PATCH] =?UTF-8?q?=F0=9F=97=A3=EF=B8=8F=20fix:=20Prevent=20`@libr?=
 =?UTF-8?q?echat/client`=20useLocalize=20from=20Overwriting=20Host=20App?=
 =?UTF-8?q?=20Language=20State=20(#12515)?=
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* directly returns the translation function without managing language state in client package

* chore: remove unused langAtom from packages/client store

* fix: add useCallback to match canonical useLocalize, add guard comment

---------

Co-authored-by: Danny Avila <danny@librechat.ai>
---
 packages/client/src/hooks/useLocalize.ts | 19 +++++++------------
 packages/client/src/store.ts             |  1 -
 2 files changed, 7 insertions(+), 13 deletions(-)

diff --git a/packages/client/src/hooks/useLocalize.ts b/packages/client/src/hooks/useLocalize.ts
index 83366cff16..cab3dd6547 100644
--- a/packages/client/src/hooks/useLocalize.ts
+++ b/packages/client/src/hooks/useLocalize.ts
@@ -1,21 +1,16 @@
-import { useEffect } from 'react';
+import { useCallback } from 'react';
 import { TOptions } from 'i18next';
-import { useAtomValue } from 'jotai';
 import { useTranslation } from 'react-i18next';
 import { resources } from '~/locales/i18n';
-import { langAtom } from '~/store';
 
 export type TranslationKeys = keyof typeof resources.en.translation;
 
+/** Language lifecycle is managed by the host app — do not add i18n.changeLanguage() calls here. */
 export default function useLocalize() {
-  const lang = useAtomValue(langAtom);
-  const { t, i18n } = useTranslation();
+  const { t } = useTranslation();
 
-  useEffect(() => {
-    if (i18n.language !== lang) {
-      i18n.changeLanguage(lang);
-    }
-  }, [lang, i18n]);
-
-  return (phraseKey: TranslationKeys, options?: TOptions) => t(phraseKey, options);
+  return useCallback(
+    (phraseKey: TranslationKeys, options?: TOptions) => t(phraseKey, options),
+    [t],
+  );
 }
diff --git a/packages/client/src/store.ts b/packages/client/src/store.ts
index 6e23be6e04..36a3f05844 100644
--- a/packages/client/src/store.ts
+++ b/packages/client/src/store.ts
@@ -1,7 +1,6 @@
 import { atom } from 'jotai';
 import { NotificationSeverity } from '~/common';
 
-export const langAtom = atom<string>('en');
 export const chatDirectionAtom = atom<string>('ltr');
 export const fontSizeAtom = atom<string>('text-base');