Fix stale language switching

src/i18n.ts

@@ -95,6 +95,7 @@ function resolveLocaleFile(lng: string): string | undefined {
  * already-loaded locales).
  */
 const loadedLocales = new Set<string>(['en']);
+let languageChangeRequest = 0;
 
 async function loadLocale(lng: string): Promise<void> {
   const file = resolveLocaleFile(lng);
@@ -134,6 +135,21 @@ async function loadLocale(lng: string): Promise<void> {
   loadedLocales.add(file);
 }
 
+/**
+ * Switch languages only after the target locale has been registered.
+ *
+ * Calling i18next.changeLanguage() first can render React components against a
+ * missing lazy-loaded bundle, leaving them stuck on fallback English until an
+ * unrelated render happens. The request counter keeps rapid clicks ordered so a
+ * slower earlier download cannot overwrite the latest selection.
+ */
+export async function changeAppLanguage(lng: string): Promise<void> {
+  const request = ++languageChangeRequest;
+  await loadLocale(lng);
+  if (request !== languageChangeRequest) return;
+  await i18n.changeLanguage(lng);
+}
+
 i18n
   .use(LanguageDetector)
   .use(initReactI18next)
@@ -161,6 +177,9 @@ i18n
       caches: ['localStorage'],
       lookupLocalStorage: 'i18nextLng',
     },
+    react: {
+      bindI18nStore: 'added',
+    },
   });
 
 // Load the locale the detector picked on startup. If it isn't English the

src/pages/LanguageSettingsPage.tsx

@@ -3,7 +3,7 @@ import { Check, Languages } from 'lucide-react';
 import { useTranslation } from 'react-i18next';
 import { PageHeader } from '@/components/PageHeader';
 import { useAppContext } from '@/hooks/useAppContext';
-import i18n, { SUPPORTED_LANGUAGES, isRTLLanguage } from '@/i18n';
+import { SUPPORTED_LANGUAGES, changeAppLanguage, isRTLLanguage } from '@/i18n';
 import { cn } from '@/lib/utils';
 
 export function LanguageSettingsPage() {
@@ -42,7 +42,7 @@ export function LanguageSettingsPage() {
 
   const handleSelect = (code: string) => {
     if (code === currentLng) return;
-    void i18n.changeLanguage(code);
+    void changeAppLanguage(code);
   };
 
   return (