diff --git a/src/renderer/src/i18n/i18n.ts b/src/renderer/src/i18n/i18n.ts
index 725a40e9aaa..e315be8ab05 100644
--- a/src/renderer/src/i18n/i18n.ts
+++ b/src/renderer/src/i18n/i18n.ts
@@ -8,6 +8,7 @@ import { initReactI18next } from 'react-i18next'
 
 import enRuntimeRequired from './en-runtime-required.json'
 import { isPseudoLocalizationLocale, pseudoLocalizeString } from './pseudo-localization'
+import { advanceTranslationResourceVersion } from './translation-resource-version'
 import { DEFAULT_LOCALE, resolveUiLocale } from './supported-languages'
 import type { SupportedUiLocale } from '../../../shared/ui-locale'
 import { isPluginUiLanguage, type UiLanguage } from '../../../shared/ui-language'
@@ -82,6 +83,10 @@ void i18n
     }
   })
 
+// Plugin packs can replace translations without changing the active language.
+i18n.store.on('added', advanceTranslationResourceVersion)
+i18n.store.on('removed', advanceTranslationResourceVersion)
+
 export function translate(key: string, fallback: string, options?: TOptions): string {
   const value = i18n.t(key, { defaultValue: fallback, ...options })
   return isPseudoLocalizationLocale(i18n.language) ? pseudoLocalizeString(value) : value
diff --git a/src/renderer/src/i18n/localized-catalog.test.ts b/src/renderer/src/i18n/localized-catalog.test.ts
new file mode 100644
index 00000000000..0dfea2dab39
--- /dev/null
+++ b/src/renderer/src/i18n/localized-catalog.test.ts
@@ -0,0 +1,114 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import { pluginLanguageResourceId } from '../../../shared/plugins/plugin-language-pack-artifact'
+import {
+  getExperimentalPaneSearchEntries,
+  getExperimentalSearchEntry
+} from '../components/settings/experimental-search'
+import { i18n, setRendererPluginLanguagePacks, setRendererUiLanguage, translate } from './i18n'
+import { createLocalizedCatalog } from './localized-catalog'
+
+const PACK_ID = 'plugin:orca-test.traditional-chinese/zh-TW' as const
+const PACK = {
+  id: PACK_ID,
+  resourceLanguage: pluginLanguageResourceId(PACK_ID),
+  pluginKey: 'orca-test.traditional-chinese',
+  locale: 'zh-TW',
+  catalog: {}
+}
+
+afterEach(async () => {
+  await i18n.changeLanguage('en')
+  setRendererPluginLanguagePacks([])
+})
+
+describe('localized catalog caching', () => {
+  it('reuses a catalog while the language and resources are unchanged', () => {
+    const builder = vi.fn(() => ({ title: translate('menu.file', 'File') }))
+    const getCatalog = createLocalizedCatalog(builder)
+
+    expect(getCatalog()).toBe(getCatalog())
+    expect(builder).toHaveBeenCalledTimes(1)
+  })
+
+  it('rebuilds after switching languages', async () => {
+    const getCatalog = createLocalizedCatalog(() => ({ title: translate('menu.file', 'File') }))
+    const english = getCatalog()
+
+    await i18n.changeLanguage('es')
+    expect(getCatalog().title).toBe('Archivo')
+
+    await i18n.changeLanguage('en')
+    expect(getCatalog()).toEqual(english)
+  })
+
+  it('retries a failed rebuild instead of returning the previous language', async () => {
+    const builder = vi.fn(() => ({ title: translate('menu.file', 'File') }))
+    const getCatalog = createLocalizedCatalog(builder)
+    expect(getCatalog().title).toBe('File')
+    await i18n.changeLanguage('es')
+    builder.mockImplementationOnce(() => {
+      throw new Error('Catalog build failed')
+    })
+
+    expect(getCatalog).toThrow('Catalog build failed')
+    expect(getCatalog().title).toBe('Archivo')
+  })
+
+  it('refreshes a cached fallback when resources are added to the active language', async () => {
+    setRendererPluginLanguagePacks([PACK])
+    await setRendererUiLanguage(PACK_ID)
+    const getCatalog = createLocalizedCatalog(() => ({ title: translate('menu.file', 'File') }))
+    expect(getCatalog().title).toBe('File')
+
+    i18n.addResourceBundle(PACK.resourceLanguage, 'translation', { menu: { file: '檔案' } })
+
+    expect(i18n.language).toBe(PACK.resourceLanguage)
+    expect(getCatalog().title).toBe('檔案')
+    expect(getCatalog()).toBe(getCatalog())
+  })
+
+  it('refreshes to the fallback when the active plugin resources are removed', async () => {
+    setRendererPluginLanguagePacks([{ ...PACK, catalog: { menu: { file: '檔案' } } }])
+    await setRendererUiLanguage(PACK_ID)
+    const getCatalog = createLocalizedCatalog(() => ({ title: translate('menu.file', 'File') }))
+    expect(getCatalog().title).toBe('檔案')
+
+    setRendererPluginLanguagePacks([])
+
+    expect(i18n.language).toBe(PACK.resourceLanguage)
+    expect(getCatalog().title).toBe('File')
+  })
+
+  it('keeps Experimental lookups usable after an in-place plugin language pack update', async () => {
+    const packWithTitles = (terminalAttention: string, newWorktreeCardStyle: string) => ({
+      ...PACK,
+      catalog: {
+        auto: {
+          components: {
+            settings: {
+              experimental: {
+                search: {
+                  '9e4ddf776d': terminalAttention,
+                  newWorktreeCardStyle: { title: newWorktreeCardStyle }
+                }
+              }
+            }
+          }
+        }
+      }
+    })
+    setRendererPluginLanguagePacks([packWithTitles('終端關注', '舊卡片樣式')])
+    await setRendererUiLanguage(PACK_ID)
+    const original = getExperimentalPaneSearchEntries()
+    expect(getExperimentalSearchEntry().terminalAttention.title).toBe('終端關注')
+    expect(getExperimentalSearchEntry().newWorktreeCardStyle.title).toBe('舊卡片樣式')
+
+    setRendererPluginLanguagePacks([packWithTitles('終端機關注', '新卡片樣式')])
+
+    expect(i18n.language).toBe(PACK.resourceLanguage)
+    expect(getExperimentalSearchEntry().terminalAttention.title).toBe('終端機關注')
+    expect(getExperimentalSearchEntry().newWorktreeCardStyle.title).toBe('新卡片樣式')
+    expect(getExperimentalPaneSearchEntries()).not.toBe(original)
+    expect(getExperimentalPaneSearchEntries()).toBe(getExperimentalPaneSearchEntries())
+  })
+})
diff --git a/src/renderer/src/i18n/localized-catalog.ts b/src/renderer/src/i18n/localized-catalog.ts
index eb35ebfd53a..fc37dcab081 100644
--- a/src/renderer/src/i18n/localized-catalog.ts
+++ b/src/renderer/src/i18n/localized-catalog.ts
@@ -1,15 +1,21 @@
 import { i18n } from './i18n'
+import { getTranslationResourceVersion } from './translation-resource-version'
 
-// Why: search metadata and catalogs call translate() during build. Caching per
-// active locale keeps lookups cheap while still refreshing after language changes.
 export function createLocalizedCatalog<T>(builder: () => T): () => T {
   let cachedLocale: string | undefined
+  let cachedResourceVersion = -1
   let cachedValue: T | undefined
 
   return () => {
-    if (cachedLocale !== i18n.language || cachedValue === undefined) {
-      cachedLocale = i18n.language
+    const resourceVersion = getTranslationResourceVersion()
+    if (
+      cachedLocale !== i18n.language ||
+      cachedResourceVersion !== resourceVersion ||
+      cachedValue === undefined
+    ) {
       cachedValue = builder()
+      cachedLocale = i18n.language
+      cachedResourceVersion = resourceVersion
     }
     return cachedValue
   }
diff --git a/src/renderer/src/i18n/translation-resource-version.ts b/src/renderer/src/i18n/translation-resource-version.ts
new file mode 100644
index 00000000000..26d608f7ce3
--- /dev/null
+++ b/src/renderer/src/i18n/translation-resource-version.ts
@@ -0,0 +1,9 @@
+let version = 0
+
+export function getTranslationResourceVersion(): number {
+  return version
+}
+
+export function advanceTranslationResourceVersion(): void {
+  version += 1
+}