diff --git a/apps/stage-pocket/src/App.vue b/apps/stage-pocket/src/App.vue
index 41c6a767a..de839f99f 100644
--- a/apps/stage-pocket/src/App.vue
+++ b/apps/stage-pocket/src/App.vue
@@ -2,6 +2,7 @@
 import { OnboardingDialog, OnboardingStepAnalyticsNotice, ToasterRoot } from '@proj-airi/stage-ui/components'
 import { useAuthProviderSync } from '@proj-airi/stage-ui/composables/use-auth-provider-sync'
 import { initializeAnalytics, isAnalyticsAvailableInBuild } from '@proj-airi/stage-ui/libs/analytics'
+import { usePiniaSynced } from '@proj-airi/stage-ui/libs/pinia'
 import { useCharacterOrchestratorStore } from '@proj-airi/stage-ui/stores/character'
 import { useDisplayModelsStore } from '@proj-airi/stage-ui/stores/display-models'
 import { useModsServerChannelStore } from '@proj-airi/stage-ui/stores/mods/api/channel-server'
@@ -35,6 +36,7 @@ const settingsAudioDeviceStore = useSettingsAudioDevice()
 const { showingSetup } = storeToRefs(onboardingStore)
 const { isDark } = useTheme()
 const cardStore = useAiriCardStore()
+const syncedPinia = usePiniaSynced()
 
 const primaryColor = computed(() => {
   return isDark.value
@@ -74,7 +76,8 @@ watch(settings.themeColorsHueDynamic, () => {
 onMounted(async () => {
   initializeAnalytics()
   await displayModelsStore.initialize()
-  cardStore.initialize()
+  cardStore.startRuntime(syncedPinia)
+  await cardStore.initialize()
 
   if (onboardingStore.needsOnboarding) {
     onboardingStore.showingSetup = true
@@ -93,6 +96,7 @@ onMounted(async () => {
 })
 
 onUnmounted(() => {
+  cardStore.disposeRuntime()
   contextBridgeStore.dispose()
 })
 
diff --git a/apps/stage-pocket/src/main.ts b/apps/stage-pocket/src/main.ts
index f7dc182ea..ba2eecb67 100644
--- a/apps/stage-pocket/src/main.ts
+++ b/apps/stage-pocket/src/main.ts
@@ -8,6 +8,7 @@ import { autoAnimatePlugin } from '@formkit/auto-animate/vue'
 import { isEnvTruthy } from '@proj-airi/stage-shared'
 import { trackButtonPlugin } from '@proj-airi/stage-ui/directives/track-button'
 import { configureAnalyticsAdapter } from '@proj-airi/stage-ui/libs/analytics'
+import { setupSynced } from '@proj-airi/stage-ui/libs/pinia'
 import { MotionPlugin } from '@vueuse/motion'
 import { createPinia } from 'pinia'
 import { setupLayouts } from 'virtual:generated-layouts'
@@ -34,6 +35,8 @@ configureAnalyticsAdapter(async (options) => {
 })
 
 const pinia = createPinia()
+const synced = setupSynced()
+pinia.use(synced.pinia)
 
 // TODO: vite-plugin-vue-layouts is long deprecated, replace with another layout solution
 const routeRecords = setupLayouts(routes as RouteRecordRaw[])
@@ -60,6 +63,7 @@ window.addEventListener('unhandledrejection', (event) => {
 installDeepLinks(router)
 
 createApp(App)
+  .use(synced.vue)
   .use(MotionPlugin)
   // TODO: Fix autoAnimatePlugin type error
   .use(autoAnimatePlugin as unknown as Plugin)
diff --git a/apps/stage-tamagotchi/src/main/libs/electron/location.test.ts b/apps/stage-tamagotchi/src/main/libs/electron/location.test.ts
index 44e5e6f3c..5800282b0 100644
--- a/apps/stage-tamagotchi/src/main/libs/electron/location.test.ts
+++ b/apps/stage-tamagotchi/src/main/libs/electron/location.test.ts
@@ -25,4 +25,24 @@ describe('withHashRoute', () => {
     const result = withHashRoute({ url: 'file:////home/workspace/project/index.html' }, '/test/inner-test')
     expect(result).toEqual({ url: `file:////home/workspace/project/index.html#/test/inner-test` })
   })
+
+  it('adds query options before the hash route for development URLs', () => {
+    expect(withHashRoute({ url: 'http://localhost:5173' }, '/about', {
+      query: { 'synced-leader': 'false' },
+    })).toEqual({
+      url: 'http://localhost:5173/?synced-leader=false#/about',
+    })
+  })
+
+  it('passes query options to Electron for packaged renderer URLs', () => {
+    expect(withHashRoute({ file: '/opt/airi/renderer/index.html' }, '/settings', {
+      query: { 'synced-leader': 'false' },
+    })).toEqual({
+      file: '/opt/airi/renderer/index.html',
+      options: {
+        hash: '/settings',
+        query: { 'synced-leader': 'false' },
+      },
+    })
+  })
 })
diff --git a/apps/stage-tamagotchi/src/main/libs/electron/location.ts b/apps/stage-tamagotchi/src/main/libs/electron/location.ts
index 5e4e97021..1c1c721a1 100644
--- a/apps/stage-tamagotchi/src/main/libs/electron/location.ts
+++ b/apps/stage-tamagotchi/src/main/libs/electron/location.ts
@@ -92,9 +92,19 @@ export async function load(window: BrowserWindow, url: string | { url: string, o
 }
 
 /**
- * A helper function to construct URL with hash route, which is commonly used in our app since we are using hash-based routing in renderer.
+ * Adds a hash route and optional query to an Electron renderer location.
+ *
+ * @example
+ * withHashRoute({ url: 'http://localhost:5173' }, '/about', {
+ *   query: { 'synced-leader': 'false' },
+ * })
+ * // => { url: 'http://localhost:5173/?synced-leader=false#/about' }
  */
-export function withHashRoute(baseUrl: string | { url: string } | { file: string }, hashRoute: string) {
+export function withHashRoute(
+  baseUrl: string | { url: string } | { file: string },
+  hashRoute: string,
+  options: Pick<LoadFileOptions, 'query'> = {},
+) {
   if (typeof baseUrl === 'object' && 'url' in baseUrl) {
     // trim `/` suffix
     const baseURLinURL = new URL(baseUrl.url)
@@ -103,12 +113,15 @@ export function withHashRoute(baseUrl: string | { url: string } | { file: string
     const trimmedPathname = pathname.endsWith('/') ? pathname.slice(0, -1) : pathname
     baseURLinURL.pathname = trimmedPathname
 
+    for (const [key, value] of Object.entries(options.query ?? {}))
+      baseURLinURL.searchParams.set(key, value)
+
     baseURLinURL.hash = hashRoute
 
     return { url: baseURLinURL.toString() } satisfies { url: string, options?: LoadURLOptions }
   }
   if (typeof baseUrl === 'object' && 'file' in baseUrl) {
-    return { file: `${baseUrl.file}`, options: { hash: hashRoute } } satisfies { file: string, options?: LoadFileOptions }
+    return { file: `${baseUrl.file}`, options: { hash: hashRoute, ...options } } satisfies { file: string, options?: LoadFileOptions }
   }
 
   // trim `/` suffix
@@ -118,6 +131,9 @@ export function withHashRoute(baseUrl: string | { url: string } | { file: string
   const trimmedPathname = pathname.endsWith('/') ? pathname.slice(0, -1) : pathname
   baseURLinURL.pathname = trimmedPathname
 
+  for (const [key, value] of Object.entries(options.query ?? {}))
+    baseURLinURL.searchParams.set(key, value)
+
   baseURLinURL.hash = hashRoute
 
   return { url: baseURLinURL.toString() } satisfies { url: string, options?: LoadURLOptions }
diff --git a/apps/stage-tamagotchi/src/main/windows/about/index.ts b/apps/stage-tamagotchi/src/main/windows/about/index.ts
index 0306df29d..52fe4abe5 100644
--- a/apps/stage-tamagotchi/src/main/windows/about/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/about/index.ts
@@ -44,7 +44,9 @@ export function setupAboutWindowReusable(params: {
       serverChannel: params.serverChannel,
     })
 
-    await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/about'))
+    await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/about', {
+      query: { 'synced-leader': 'false' },
+    }))
 
     return window
   }).getWindow
diff --git a/apps/stage-tamagotchi/src/main/windows/caption/index.ts b/apps/stage-tamagotchi/src/main/windows/caption/index.ts
index 0b822d44c..5e254ee74 100644
--- a/apps/stage-tamagotchi/src/main/windows/caption/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/caption/index.ts
@@ -344,7 +344,9 @@ export function setupCaptionWindowManager(params: {
 
     const cleanupGetAttached = defineInvokeHandler(context, captionGetIsFollowingWindow, async () => isFollowing)
 
-    await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/caption'))
+    await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/caption', {
+      query: { 'synced-leader': 'false' },
+    }))
 
     try {
       context.emit(captionIsFollowingWindowChanged, isFollowing)
diff --git a/apps/stage-tamagotchi/src/main/windows/chat/index.ts b/apps/stage-tamagotchi/src/main/windows/chat/index.ts
index c3dca9ddc..52aede3ca 100644
--- a/apps/stage-tamagotchi/src/main/windows/chat/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/chat/index.ts
@@ -44,7 +44,12 @@ export function setupChatWindowReusableFunc(params: {
       i18n: params.i18n,
     })
 
-    await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/chat'))
+    await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/chat', {
+      query: {
+        'stage-runtime': 'minimal',
+        'synced-leader': 'false',
+      },
+    }))
 
     return window
   }).getWindow
diff --git a/apps/stage-tamagotchi/src/main/windows/dashboard/index.ts b/apps/stage-tamagotchi/src/main/windows/dashboard/index.ts
index cdb4205cc..c52a9498e 100644
--- a/apps/stage-tamagotchi/src/main/windows/dashboard/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/dashboard/index.ts
@@ -137,7 +137,9 @@ export async function setupDashboardWindow(params: {
     serverChannel: params.serverChannel,
   })
 
-  await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/dashboard'))
+  await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/dashboard', {
+    query: { 'synced-leader': 'false' },
+  }))
 
   /**
    * This is a know issue (or expected behavior maybe) to Electron.
diff --git a/apps/stage-tamagotchi/src/main/windows/desktop-overlay/index.ts b/apps/stage-tamagotchi/src/main/windows/desktop-overlay/index.ts
index e2c81e92c..eef5f658f 100644
--- a/apps/stage-tamagotchi/src/main/windows/desktop-overlay/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/desktop-overlay/index.ts
@@ -123,6 +123,7 @@ export async function setupDesktopOverlayWindow(params: {
       isDesktopOverlayPollHeartbeatEnabled()
         ? `/desktop-overlay?${desktopOverlayPollHeartbeatQueryParam}=1`
         : '/desktop-overlay',
+      { query: { 'synced-leader': 'false' } },
     ),
   )
 
diff --git a/apps/stage-tamagotchi/src/main/windows/devtools/index.ts b/apps/stage-tamagotchi/src/main/windows/devtools/index.ts
index ef635d6f8..17e9bf965 100644
--- a/apps/stage-tamagotchi/src/main/windows/devtools/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/devtools/index.ts
@@ -50,7 +50,9 @@ export function setupDevtoolsWindow(): DevtoolsWindowManager {
       })
       protectPrivilegedWindowNavigation(window)
 
-      await load(window, withHashRoute(rendererBase, route))
+      await load(window, withHashRoute(rendererBase, route, {
+        query: { 'synced-leader': 'false' },
+      }))
       return window
     })
 
diff --git a/apps/stage-tamagotchi/src/main/windows/editor/index.ts b/apps/stage-tamagotchi/src/main/windows/editor/index.ts
index f63caf13c..b724e6779 100644
--- a/apps/stage-tamagotchi/src/main/windows/editor/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/editor/index.ts
@@ -55,7 +55,12 @@ export function setupEditorWindowManager(params: {
       i18n: params.i18n,
       serverChannel: params.serverChannel,
     })
-    await load(window, withHashRoute(rendererBase, '/editor'))
+    await load(window, withHashRoute(rendererBase, '/editor', {
+      query: {
+        'stage-runtime': 'minimal',
+        'synced-leader': 'false',
+      },
+    }))
 
     return window
   })
diff --git a/apps/stage-tamagotchi/src/main/windows/inlay/index.ts b/apps/stage-tamagotchi/src/main/windows/inlay/index.ts
index 5e5c431a7..154d809ae 100644
--- a/apps/stage-tamagotchi/src/main/windows/inlay/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/inlay/index.ts
@@ -66,7 +66,9 @@ export async function setupInlayWindow(params: {
 
   await setupInlayWindowInvokes({ inlayWindow: window, serverChannel: params.serverChannel, i18n: params.i18n })
 
-  await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/inlay'))
+  await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/inlay', {
+    query: { 'synced-leader': 'false' },
+  }))
 
   return window
 }
diff --git a/apps/stage-tamagotchi/src/main/windows/main/index.ts b/apps/stage-tamagotchi/src/main/windows/main/index.ts
index 708736e77..6e9b32590 100644
--- a/apps/stage-tamagotchi/src/main/windows/main/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/main/index.ts
@@ -29,7 +29,7 @@ import icon from '../../../../resources/icon.png?asset'
 
 import { electronStartDraggingWindow } from '../../../shared/eventa'
 import { onAppBeforeQuit } from '../../libs/bootkit/lifecycle'
-import { baseUrl, getElectronMainDirname, load } from '../../libs/electron/location'
+import { baseUrl, getElectronMainDirname, load, withHashRoute } from '../../libs/electron/location'
 import { createConfig } from '../../libs/electron/persistence'
 import { protectPrivilegedWindowNavigation, transparentWindowConfig } from '../shared'
 import { setupMainWindowElectronInvokes } from './rpc/index.electron'
@@ -186,7 +186,9 @@ export async function setupMainWindow(params: {
     onboardingWindowManager: params.onboardingWindowManager,
   })
 
-  await load(window, baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')))
+  await load(window, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/', {
+    query: { 'synced-leader': 'true' },
+  }))
 
   /**
    * This is a know issue (or expected behavior maybe) to Electron.
diff --git a/apps/stage-tamagotchi/src/main/windows/notice/index.ts b/apps/stage-tamagotchi/src/main/windows/notice/index.ts
index 7087e4de4..f1acb1e26 100644
--- a/apps/stage-tamagotchi/src/main/windows/notice/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/notice/index.ts
@@ -47,7 +47,9 @@ export function setupNoticeWindowManager(params: {
 
   async function loadNoticeRoute(window: BrowserWindow, payload: RequestWindowPayload & { id: string }) {
     const routeWithId = `${payload.route}?id=${payload.id}`
-    await load(window, withHashRoute(rendererBase, routeWithId))
+    await load(window, withHashRoute(rendererBase, routeWithId, {
+      query: { 'synced-leader': 'false' },
+    }))
   }
 
   const manager = createReferencedWindowManager({
diff --git a/apps/stage-tamagotchi/src/main/windows/onboarding/index.ts b/apps/stage-tamagotchi/src/main/windows/onboarding/index.ts
index cbb1d71c9..722f8981f 100644
--- a/apps/stage-tamagotchi/src/main/windows/onboarding/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/onboarding/index.ts
@@ -74,7 +74,9 @@ export function setupOnboardingWindowManager(params: {
     await setupBaseWindowElectronInvokes({ context, window: newWindow, i18n: params.i18n, serverChannel: params.serverChannel })
     createAuthService({ context, window: newWindow })
 
-    await load(newWindow, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/onboarding'))
+    await load(newWindow, withHashRoute(baseUrl(resolve(getElectronMainDirname(), '..', 'renderer')), '/onboarding', {
+      query: { 'synced-leader': 'false' },
+    }))
 
     newWindow.on('closed', () => {
       for (const cb of closeCallbacks) {
diff --git a/apps/stage-tamagotchi/src/main/windows/settings/index.ts b/apps/stage-tamagotchi/src/main/windows/settings/index.ts
index 2ffc7310e..fe449364e 100644
--- a/apps/stage-tamagotchi/src/main/windows/settings/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/settings/index.ts
@@ -78,7 +78,9 @@ export function setupSettingsWindowReusableFunc(params: {
       spotlightWindow: params.spotlightWindow,
     })
 
-    await load(window, withHashRoute(rendererBase, currentRoute))
+    await load(window, withHashRoute(rendererBase, currentRoute, {
+      query: { 'synced-leader': 'false' },
+    }))
 
     window.on('closed', () => {
       if (settingsContext)
diff --git a/apps/stage-tamagotchi/src/main/windows/spotlight/index.ts b/apps/stage-tamagotchi/src/main/windows/spotlight/index.ts
index 36e28083f..4979f45b1 100644
--- a/apps/stage-tamagotchi/src/main/windows/spotlight/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/spotlight/index.ts
@@ -140,7 +140,12 @@ export function setupSpotlightWindowManager(params: {
       showNotification(payload.body, () => void openChatWindowFromNotification())
     })
 
-    await load(window, withHashRoute(rendererBase, '/spotlight'))
+    await load(window, withHashRoute(rendererBase, '/spotlight', {
+      query: {
+        'stage-runtime': 'minimal',
+        'synced-leader': 'false',
+      },
+    }))
 
     return window
   })
diff --git a/apps/stage-tamagotchi/src/main/windows/widgets/index.ts b/apps/stage-tamagotchi/src/main/windows/widgets/index.ts
index 997405c0d..0a3cceb8a 100644
--- a/apps/stage-tamagotchi/src/main/windows/widgets/index.ts
+++ b/apps/stage-tamagotchi/src/main/windows/widgets/index.ts
@@ -440,7 +440,9 @@ export function setupWidgetsWindowManager(params: {
   }
 
   async function loadWithRoute(window: BrowserWindow, route: string) {
-    await load(window, withHashRoute(rendererBase, route))
+    await load(window, withHashRoute(rendererBase, route, {
+      query: { 'synced-leader': 'false' },
+    }))
     currentRoute = route
   }
 
diff --git a/apps/stage-tamagotchi/src/renderer/App.vue b/apps/stage-tamagotchi/src/renderer/App.vue
index 845388cc4..b3b415108 100644
--- a/apps/stage-tamagotchi/src/renderer/App.vue
+++ b/apps/stage-tamagotchi/src/renderer/App.vue
@@ -62,7 +62,7 @@ import {
   useTamagotchiMcpToolsStore,
   useTamagotchiPluginToolsStore,
 } from './stores/tools'
-import { resolveInitialWindowRoutePath } from './window-route'
+import { resolveInitialRendererRoutePath, resolveRendererWindowContext } from './window-context'
 
 const { isDark: dark } = useTheme()
 const settingsStore = useSettings()
@@ -73,20 +73,17 @@ const chatSessionStore = useChatSessionStore()
 const context = useElectronEventaContext()
 const getMainLocale = useElectronEventaInvoke(i18nGetLocale)
 const setLocale = useElectronEventaInvoke(i18nSetLocale)
-const initialWindowRoutePath = resolveInitialWindowRoutePath(route.path)
+const windowContext = resolveRendererWindowContext()
+const initialRoutePath = resolveInitialRendererRoutePath(route.path)
 useChatStore()
 const builtinToolsStore = useTamagotchiBuiltinToolsStore()
 const mcpToolsStore = useTamagotchiMcpToolsStore()
 const pluginToolsStore = useTamagotchiPluginToolsStore()
 const syncedPinia = usePiniaSynced()
 chatSessionStore.setCloudSyncOwnership(syncedPinia.isLeader())
-const isSpotlightWindowRoute = initialWindowRoutePath === '/spotlight'
-const isSettingsWindowRoute = initialWindowRoutePath === '/settings' || initialWindowRoutePath.startsWith('/settings/')
-const isEditorWindowRoute = initialWindowRoutePath === '/editor'
+const isSpotlightWindow = initialRoutePath === '/spotlight'
+const isSettingsWindow = initialRoutePath === '/settings' || initialRoutePath.startsWith('/settings/')
 
-// Every renderer participates in leader election. Keep provider state ready in
-// auxiliary windows so a newly elected leader can execute chat actions after
-// the previous window closes.
 useAuthProviderSync()
 
 async function refreshPluginRuntimeTools() {
@@ -98,8 +95,8 @@ async function refreshPluginRuntimeTools() {
   }
 }
 
-// Every renderer creates the runtime tool stores because every renderer can
-// become the leader. Only the leader discovers tools and keeps executors.
+// Every renderer creates the runtime tool stores for synchronized state. Only
+// the main Stage renderer discovers tools and keeps executors.
 const stopLeadershipListener = syncedPinia.onLeadershipChange((isLeader) => {
   chatSessionStore.setCloudSyncOwnership(isLeader)
   if (!isLeader)
@@ -139,9 +136,8 @@ function createFullStageRuntime() {
   const reportPluginCapability = useElectronEventaInvoke(electronPluginUpdateCapability)
   const getGodotStageStatus = useElectronEventaInvoke(electronGodotStageGetStatus)
   const syncArtistryConfig = useElectronEventaInvoke(artistrySyncConfig)
-  const isAuxiliaryChatRoute = initialWindowRoutePath === '/chat'
-  const isGodotStageRoute = () => route.path === '/' || route.path.startsWith('/settings')
-  const isWidgetsWindowRoute = () => route.path === '/widgets'
+  const usesGodotStage = initialRoutePath === '/' || initialRoutePath.startsWith('/settings')
+  const isWidgetsWindow = initialRoutePath === '/widgets'
 
   function syncGodotStageRenderer(state: { state: 'stopped' | 'starting' | 'running' | 'stopping' | 'error' }) {
     if (state.state === 'running') {
@@ -155,12 +151,13 @@ function createFullStageRuntime() {
 
   usePerfTracerBridgeStore()
   initializeStageThreeRuntimeTraceBridge()
+  // The main process returns the callback only to the renderer that started
+  // sign-in. Each login-capable window listens locally, while the synchronized
+  // auth action still executes once in the main Stage leader.
   initializeElectronAuthCallbackBridge()
   void stageWindowLifecycleStore.initializeWindowLifecycleBridge()
 
-  watch(() => route.path, () => {
-    contextBridgeStore.setSparkNotifyHostRole(isWidgetsWindowRoute() ? 'client' : 'main')
-  }, { immediate: true })
+  contextBridgeStore.setSparkNotifyHostRole(isWidgetsWindow ? 'client' : 'main')
 
   // NOTICE: register plugin host bridge during setup to avoid race with pages using it in immediate watchers.
   pluginHostInspectorStore.setBridge({
@@ -217,13 +214,14 @@ function createFullStageRuntime() {
     async initialize() {
       initializeAnalytics()
       await displayModelsStore.initialize()
-      cardStore.initialize()
+      cardStore.startRuntime(syncedPinia)
+      await cardStore.initialize()
 
       await displayModelsStore.loadDisplayModelsFromIndexedDB()
       await settingsStore.initializeStageModel()
       await settingsAudioDeviceStore.initialize()
 
-      if (isGodotStageRoute()) {
+      if (usesGodotStage) {
         try {
           syncGodotStageRenderer(await getGodotStageStatus())
         }
@@ -241,12 +239,10 @@ function createFullStageRuntime() {
         token: serverChannelConfig.authToken || undefined,
         possibleEvents: ['ui:configure'],
       }).catch(err => console.error('Failed to initialize Mods Server Channel in App.vue:', err))
-      if (!isAuxiliaryChatRoute) {
-        contextBridgeStore.initialize()
-        if (!isWidgetsWindowRoute()) {
-          characterOrchestratorStore.initialize()
-          await startTrackingCursorPoint()
-        }
+      contextBridgeStore.initialize()
+      if (!isWidgetsWindow) {
+        characterOrchestratorStore.initialize()
+        await startTrackingCursorPoint()
       }
 
       defineInvokeHandler(context.value, pluginProtocolListProviders, async () => listProvidersForPluginHost())
@@ -264,13 +260,15 @@ function createFullStageRuntime() {
       inferencePreload.triggerPreload()
     },
     dispose() {
-      if (!isAuxiliaryChatRoute)
-        contextBridgeStore.dispose()
+      cardStore.disposeRuntime()
+      contextBridgeStore.dispose()
     },
   }
 }
 
-const fullStageRuntime = isSpotlightWindowRoute || isEditorWindowRoute ? null : createFullStageRuntime()
+const fullStageRuntime = windowContext.stageRuntime === 'full'
+  ? createFullStageRuntime()
+  : null
 
 const { restore: restoreLocale } = useLanguage(language, getMainLocale, setLocale)
 
@@ -279,7 +277,7 @@ watch(dark, () => updateThemeColor(), { immediate: true })
 watch(route, () => updateThemeColor(), { immediate: true })
 onMounted(() => updateThemeColor())
 
-if (isSettingsWindowRoute) {
+if (isSettingsWindow) {
   context.value.on(electronSettingsNavigate, (event) => {
     const targetRoute = event?.body?.route
     if (!targetRoute || route.fullPath === targetRoute) {
@@ -324,7 +322,7 @@ onUnmounted(() => {
   <ToasterRoot @close="id => toast.dismiss(id)">
     <Toaster />
   </ToasterRoot>
-  <ResizeHandler v-if="!isSpotlightWindowRoute" />
+  <ResizeHandler v-if="!isSpotlightWindow" />
   <RouterView />
 </template>
 
diff --git a/apps/stage-tamagotchi/src/renderer/main.ts b/apps/stage-tamagotchi/src/renderer/main.ts
index a42a0f198..9354bce3b 100644
--- a/apps/stage-tamagotchi/src/renderer/main.ts
+++ b/apps/stage-tamagotchi/src/renderer/main.ts
@@ -18,6 +18,7 @@ import { handleHotUpdate, routes } from 'vue-router/auto-routes'
 import App from './App.vue'
 
 import { i18n } from './modules/i18n'
+import { resolveRendererWindowContext } from './window-context'
 
 import '@unocss/reset/tailwind.css'
 import 'splitpanes/dist/splitpanes.css'
@@ -45,7 +46,9 @@ configureAnalyticsAdapter(async (options) => {
 })
 
 const pinia = createPinia()
-const synced = setupSynced()
+const synced = setupSynced({
+  leadership: resolveRendererWindowContext().leadership,
+})
 pinia.use(synced.pinia)
 pinia.use(piniaPluginTracing)
 
diff --git a/apps/stage-tamagotchi/src/renderer/window-context.test.ts b/apps/stage-tamagotchi/src/renderer/window-context.test.ts
new file mode 100644
index 000000000..cebfa5314
--- /dev/null
+++ b/apps/stage-tamagotchi/src/renderer/window-context.test.ts
@@ -0,0 +1,44 @@
+import { describe, expect, it } from 'vitest'
+
+import { resolveInitialRendererRoutePath, resolveRendererWindowContext } from './window-context'
+
+describe('resolveInitialRendererRoutePath', () => {
+  // ROOT CAUSE:
+  //
+  // Vue Router reports `/` during App setup, before it hydrates the hash
+  // route. Window-specific setup therefore used the main-window behavior in
+  // widgets and settings renderers.
+  //
+  // https://github.com/moeru-ai/airi/pull/2304
+  it('uses the hash route before Vue Router hydrates', () => {
+    expect(resolveInitialRendererRoutePath('/', '#/widgets')).toBe('/widgets')
+    expect(resolveInitialRendererRoutePath('/', '#/settings/providers?source=tray')).toBe('/settings/providers')
+  })
+
+  it('uses the router path when no hash route exists', () => {
+    expect(resolveInitialRendererRoutePath('/settings/data', '')).toBe('/settings/data')
+  })
+})
+
+describe('resolveRendererWindowContext', () => {
+  it('assigns synchronized leadership from the explicit query', () => {
+    expect(resolveRendererWindowContext('?synced-leader=true')).toMatchObject({
+      leadership: 'leader-only',
+    })
+    expect(resolveRendererWindowContext('?synced-leader=false')).toMatchObject({
+      leadership: 'follower-only',
+    })
+  })
+
+  it('uses the full Stage runtime unless the query selects the minimal runtime', () => {
+    expect(resolveRendererWindowContext('?synced-leader=true').stageRuntime).toBe('full')
+    expect(resolveRendererWindowContext('?synced-leader=false').stageRuntime).toBe('full')
+    expect(resolveRendererWindowContext('?synced-leader=false&stage-runtime=minimal').stageRuntime).toBe('minimal')
+  })
+
+  it('rejects a renderer URL without an explicit leadership query', () => {
+    expect(() => resolveRendererWindowContext('')).toThrow('Missing synced-leader query')
+    expect(() => resolveRendererWindowContext('?synced-leader=unknown')).toThrow('Invalid synced-leader query: unknown')
+    expect(() => resolveRendererWindowContext('?synced-leader=false&stage-runtime=unknown')).toThrow('Invalid stage-runtime query: unknown')
+  })
+})
diff --git a/apps/stage-tamagotchi/src/renderer/window-context.ts b/apps/stage-tamagotchi/src/renderer/window-context.ts
new file mode 100644
index 000000000..602e2b3b0
--- /dev/null
+++ b/apps/stage-tamagotchi/src/renderer/window-context.ts
@@ -0,0 +1,51 @@
+import type { LeadershipMode } from '@proj-airi/stage-ui/libs/pinia'
+
+/** Describes the synchronization and Stage runtime policy for one renderer. */
+export interface RendererWindowContext {
+  /** Determines whether this renderer can own synchronized actions. */
+  leadership: LeadershipMode
+  /** Determines whether this renderer initializes Stage integrations. */
+  stageRuntime: 'full' | 'minimal'
+}
+
+function normalizeRoutePath(routePath: string) {
+  const [path = ''] = routePath.split(/[?#]/)
+  return path || '/'
+}
+
+/**
+ * Resolves the initial renderer route before Vue Router hydrates the hash.
+ *
+ * @example
+ * resolveInitialRendererRoutePath('/', '#/widgets?source=tray')
+ * // => '/widgets'
+ */
+export function resolveInitialRendererRoutePath(routePath: string, hash = globalThis.location?.hash ?? ''): string {
+  const hashPath = hash.startsWith('#') ? hash.slice(1) : ''
+  return normalizeRoutePath(hashPath || routePath)
+}
+
+/**
+ * Resolves renderer ownership from the query that the main process supplies.
+ *
+ * @example
+ * resolveRendererWindowContext('?synced-leader=false&stage-runtime=minimal')
+ * // => { leadership: 'follower-only', stageRuntime: 'minimal' }
+ */
+export function resolveRendererWindowContext(search = globalThis.location?.search ?? ''): RendererWindowContext {
+  const query = new URLSearchParams(search)
+  const syncedLeader = query.get('synced-leader')
+  if (syncedLeader === null)
+    throw new TypeError('Missing synced-leader query')
+  if (syncedLeader !== 'true' && syncedLeader !== 'false')
+    throw new TypeError(`Invalid synced-leader query: ${syncedLeader}`)
+
+  const stageRuntime = query.get('stage-runtime')
+  if (stageRuntime !== null && stageRuntime !== 'minimal')
+    throw new TypeError(`Invalid stage-runtime query: ${stageRuntime}`)
+
+  return {
+    leadership: syncedLeader === 'true' ? 'leader-only' : 'follower-only',
+    stageRuntime: stageRuntime === 'minimal' ? 'minimal' : 'full',
+  }
+}
diff --git a/apps/stage-tamagotchi/src/renderer/window-route.test.ts b/apps/stage-tamagotchi/src/renderer/window-route.test.ts
deleted file mode 100644
index f22b14d78..000000000
--- a/apps/stage-tamagotchi/src/renderer/window-route.test.ts
+++ /dev/null
@@ -1,13 +0,0 @@
-import { describe, expect, it } from 'vitest'
-
-import { resolveInitialWindowRoutePath } from './window-route'
-
-describe('resolveInitialWindowRoutePath', () => {
-  it('uses the hash route before Vue Router hydrates', () => {
-    expect(resolveInitialWindowRoutePath('/', '#/chat?source=tray')).toBe('/chat')
-  })
-
-  it('uses the router path when no hash route exists', () => {
-    expect(resolveInitialWindowRoutePath('/settings/data', '')).toBe('/settings/data')
-  })
-})
diff --git a/apps/stage-tamagotchi/src/renderer/window-route.ts b/apps/stage-tamagotchi/src/renderer/window-route.ts
deleted file mode 100644
index cd5b307c2..000000000
--- a/apps/stage-tamagotchi/src/renderer/window-route.ts
+++ /dev/null
@@ -1,10 +0,0 @@
-function normalizeRoutePath(routePath: string) {
-  const [path = ''] = routePath.split(/[?#]/)
-  return path || '/'
-}
-
-/** Resolves the initial hash route before Vue Router hydrates `route.path`. */
-export function resolveInitialWindowRoutePath(routePath: string, hash = globalThis.location?.hash ?? '') {
-  const hashPath = hash.startsWith('#') ? hash.slice(1) : ''
-  return normalizeRoutePath(hashPath || routePath)
-}
diff --git a/apps/stage-web/src/App.vue b/apps/stage-web/src/App.vue
index 96aae0266..4a3ec9e3c 100644
--- a/apps/stage-web/src/App.vue
+++ b/apps/stage-web/src/App.vue
@@ -89,7 +89,8 @@ watch(settings.themeColorsHueDynamic, () => {
 onMounted(async () => {
   initializeAnalytics()
   await displayModelsStore.initialize()
-  cardStore.initialize()
+  cardStore.startRuntime(syncedPinia)
+  await cardStore.initialize()
 
   if (onboardingStore.needsOnboarding) {
     onboardingStore.showingSetup = true
@@ -110,6 +111,7 @@ onMounted(async () => {
 
 onUnmounted(() => {
   stopLeadershipListener()
+  cardStore.disposeRuntime()
   contextBridgeStore.dispose()
 })
 
diff --git a/packages/stage-ui/src/composables/use-auth-provider-sync.test.ts b/packages/stage-ui/src/composables/use-auth-provider-sync.test.ts
index e8fba0ed8..78a7b4f30 100644
--- a/packages/stage-ui/src/composables/use-auth-provider-sync.test.ts
+++ b/packages/stage-ui/src/composables/use-auth-provider-sync.test.ts
@@ -4,6 +4,7 @@ import { OFFICIAL_TRANSCRIPTION_PROVIDER_ID } from '../libs/providers'
 import { useAuthProviderSync } from './use-auth-provider-sync'
 
 const syncState = vi.hoisted(() => ({
+  isLeader: false,
   authenticatedHook: undefined as (() => Promise<void>) | undefined,
   logoutHook: undefined as (() => void) | undefined,
   activeProvider: '',
@@ -20,6 +21,8 @@ const syncState = vi.hoisted(() => ({
 const syncMocks = vi.hoisted(() => ({
   initializeAuth: vi.fn(async () => {}),
   leadershipHook: undefined as ((isLeader: boolean) => void) | undefined,
+  disposeAuthenticatedHook: vi.fn(),
+  disposeLogoutHook: vi.fn(),
   forceProviderConfigured: vi.fn(),
   setProviderUnconfigured: vi.fn(),
   setProviderAvailabilityOverride: vi.fn(),
@@ -35,6 +38,7 @@ vi.mock('../libs/auth', () => ({
 
 vi.mock('../libs/pinia', () => ({
   usePiniaSynced: () => ({
+    isLeader: () => syncState.isLeader,
     onLeadershipChange: (hook: (isLeader: boolean) => void) => {
       syncMocks.leadershipHook = hook
       return vi.fn()
@@ -51,9 +55,17 @@ vi.mock('../stores/auth', () => ({
   useAuthStore: () => ({
     onAuthenticated: (hook: () => Promise<void>) => {
       syncState.authenticatedHook = hook
+      return () => {
+        syncState.authenticatedHook = undefined
+        syncMocks.disposeAuthenticatedHook()
+      }
     },
     onLogout: (hook: () => void) => {
       syncState.logoutHook = hook
+      return () => {
+        syncState.logoutHook = undefined
+        syncMocks.disposeLogoutHook()
+      }
     },
   }),
 }))
@@ -118,6 +130,7 @@ vi.mock('./use-analytics', () => ({
 
 describe('useAuthProviderSync', () => {
   beforeEach(() => {
+    syncState.isLeader = false
     syncState.authenticatedHook = undefined
     syncState.logoutHook = undefined
     syncMocks.leadershipHook = undefined
@@ -134,17 +147,57 @@ describe('useAuthProviderSync', () => {
     syncMocks.fetchModelsForProvider.mockResolvedValue([])
   })
 
-  it('restores auth initialization when this renderer becomes the leader', async () => {
+  it('starts auth initialization when this renderer becomes the leader', async () => {
     useAuthProviderSync()
-    expect(syncMocks.initializeAuth).toHaveBeenCalledTimes(1)
+    expect(syncMocks.initializeAuth).not.toHaveBeenCalled()
 
+    syncState.isLeader = true
     syncMocks.leadershipHook?.(true)
     await Promise.resolve()
 
+    expect(syncMocks.initializeAuth).toHaveBeenCalledTimes(1)
+  })
+
+  it('does not activate providers in a follower renderer', () => {
+    useAuthProviderSync()
+
+    expect(syncState.authenticatedHook).toBeUndefined()
+    expect(syncMocks.initializeAuth).not.toHaveBeenCalled()
+    expect(syncMocks.forceProviderConfigured).not.toHaveBeenCalled()
+  })
+
+  // ROOT CAUSE:
+  //
+  // A renderer kept its auth hooks after it lost leadership. Those hooks
+  // could mutate provider state while the new leader handled the same auth
+  // transition.
+  //
+  // https://github.com/moeru-ai/airi/pull/2304
+  it('removes auth hooks on demotion and restores them after reacquiring leadership', () => {
+    syncState.isLeader = true
+    useAuthProviderSync()
+
+    expect(syncState.authenticatedHook).toBeDefined()
+    expect(syncState.logoutHook).toBeDefined()
+
+    syncState.isLeader = false
+    syncMocks.leadershipHook?.(false)
+
+    expect(syncMocks.disposeAuthenticatedHook).toHaveBeenCalledTimes(1)
+    expect(syncMocks.disposeLogoutHook).toHaveBeenCalledTimes(1)
+    expect(syncState.authenticatedHook).toBeUndefined()
+    expect(syncState.logoutHook).toBeUndefined()
+
+    syncState.isLeader = true
+    syncMocks.leadershipHook?.(true)
+
     expect(syncMocks.initializeAuth).toHaveBeenCalledTimes(2)
+    expect(syncState.authenticatedHook).toBeDefined()
+    expect(syncState.logoutHook).toBeDefined()
   })
 
   it('activates every official provider after direct sign-in when no custom provider is selected', async () => {
+    syncState.isLeader = true
     useAuthProviderSync()
 
     await syncState.authenticatedHook?.()
@@ -165,6 +218,7 @@ describe('useAuthProviderSync', () => {
     // The auth hook marked the session synchronized before model and streaming
     // provider bootstrap completed. A transient failure therefore made every
     // later authentication notification return early for the whole session.
+    syncState.isLeader = true
     syncMocks.fetchModelsForProvider.mockImplementation(async (providerId: string) => {
       if (providerId === 'official-provider-speech-streaming')
         throw new Error('temporary catalog failure')
diff --git a/packages/stage-ui/src/composables/use-auth-provider-sync.ts b/packages/stage-ui/src/composables/use-auth-provider-sync.ts
index ddff649ad..b092114d1 100644
--- a/packages/stage-ui/src/composables/use-auth-provider-sync.ts
+++ b/packages/stage-ui/src/composables/use-auth-provider-sync.ts
@@ -38,15 +38,39 @@ const STREAMING_SPEECH_PROVIDER_ID = 'official-provider-speech-streaming'
  * auxiliary windows do not depend on the transient Stage scene lifecycle.
  */
 export function useAuthProviderSync() {
-  void initializeAuth()
+  const syncedPinia = usePiniaSynced()
+  let leaderSyncInitialized = false
+  let disposeAuthenticatedProviderSync: (() => void) | undefined
 
-  // A replacement leader has no active refresh timer. Restore the auth
-  // lifecycle when this renderer acquires leadership after another closes.
-  usePiniaSynced().onLeadershipChange((isLeader) => {
+  function initializeLeaderSync() {
+    if (!syncedPinia.isLeader() || leaderSyncInitialized)
+      return
+
+    leaderSyncInitialized = true
+    void initializeAuth()
+    disposeAuthenticatedProviderSync = setupAuthenticatedProviderSync()
+  }
+
+  function disposeLeaderSync() {
+    if (!leaderSyncInitialized)
+      return
+
+    disposeAuthenticatedProviderSync?.()
+    disposeAuthenticatedProviderSync = undefined
+    leaderSyncInitialized = false
+  }
+
+  syncedPinia.onLeadershipChange((isLeader) => {
     if (isLeader)
-      void initializeAuth()
+      initializeLeaderSync()
+    else
+      disposeLeaderSync()
   })
 
+  initializeLeaderSync()
+}
+
+function setupAuthenticatedProviderSync() {
   const authStore = useAuthStore()
   const providersStore = useProviderStore()
   const consciousnessStore = useConsciousnessStore()
@@ -62,7 +86,7 @@ export function useAuthProviderSync() {
   let authGeneration = 0
   let syncInFlight: Promise<void> | undefined
 
-  authStore.onAuthenticated(async () => {
+  const stopAuthenticatedHook = authStore.onAuthenticated(async () => {
     if (hasSynced)
       return
 
@@ -202,7 +226,7 @@ export function useAuthProviderSync() {
     speechStore.activeSpeechVoiceId = ''
   }
 
-  authStore.onLogout(() => {
+  const stopLogoutHook = authStore.onLogout(() => {
     authGeneration++
     hasSynced = false
 
@@ -249,4 +273,10 @@ export function useAuthProviderSync() {
       }
     }
   })
+
+  return () => {
+    authGeneration++
+    stopAuthenticatedHook()
+    stopLogoutHook()
+  }
 }
diff --git a/packages/stage-ui/src/libs/pinia/setup-synced.ts b/packages/stage-ui/src/libs/pinia/setup-synced.ts
index 16d16940c..dc0d58d24 100644
--- a/packages/stage-ui/src/libs/pinia/setup-synced.ts
+++ b/packages/stage-ui/src/libs/pinia/setup-synced.ts
@@ -1,10 +1,12 @@
 import type { PiniaPlugin } from 'pinia'
-import type { SyncedPiniaRuntime } from 'pinia-plugin-synced'
+import type { SyncedOptions, SyncedPiniaRuntime } from 'pinia-plugin-synced'
 import type { InjectionKey, Plugin } from 'vue'
 
 import { createSyncedPiniaPlugin } from 'pinia-plugin-synced'
 import { inject } from 'vue'
 
+export type { LeadershipMode } from 'pinia-plugin-synced'
+
 /** Provides the synchronization runtime installed by {@link setupSynced}. */
 export const injectKeyPiniaSynced: InjectionKey<SyncedPiniaRuntime> = Symbol('stage-synced-pinia-runtime')
 
@@ -14,13 +16,17 @@ export const injectKeyPiniaSynced: InjectionKey<SyncedPiniaRuntime> = Symbol('st
  * Install both plugins on the same application. The Vue plugin provides the
  * runtime to components and releases its election channel when the page or
  * Vue application ends.
+ *
+ * @param options Leadership policy for this renderer. Defaults to the plugin's
+ * follower-preferred mode.
  */
-export function setupSynced(): { pinia: PiniaPlugin, vue: Plugin } {
+export function setupSynced(options: Pick<SyncedOptions, 'leadership'> = {}): { pinia: PiniaPlugin, vue: Plugin } {
   const runtime = createSyncedPiniaPlugin({
     namespace: 'airi:stage:pinia',
     // Chat and image-generation actions can outlive the plugin's 30-second
     // default. Keep the timeout aligned with the previous Electron coordinator.
     callTimeout: 5 * 60 * 1000,
+    ...options,
     onError(error) {
       console.error('[stage-synced-pinia] Synchronization failed:', error)
     },
diff --git a/packages/stage-ui/src/stores/modules/airi-card.test.ts b/packages/stage-ui/src/stores/modules/airi-card.test.ts
index 1084f974e..0d9267172 100644
--- a/packages/stage-ui/src/stores/modules/airi-card.test.ts
+++ b/packages/stage-ui/src/stores/modules/airi-card.test.ts
@@ -1,3 +1,5 @@
+import type { SyncedPiniaRuntime } from 'pinia-plugin-synced'
+
 import type { AiriCard } from './airi-card'
 
 import { createPinia, setActivePinia } from 'pinia'
@@ -6,6 +8,22 @@ import { beforeEach, describe, expect, it, vi } from 'vitest'
 import { useSettingsStageModel } from '../settings/stage-model'
 import { useAiriCardStore } from './airi-card'
 
+const syncedRuntime = {
+  isLeader: false,
+  leadershipListener: undefined as ((isLeader: boolean) => void) | undefined,
+  stopLeadershipListener: vi.fn(() => {
+    syncedRuntime.leadershipListener = undefined
+  }),
+}
+
+const syncedPinia = {
+  onLeadershipChange(listener) {
+    syncedRuntime.leadershipListener = listener
+    listener(syncedRuntime.isLeader)
+    return syncedRuntime.stopLeadershipListener
+  },
+} satisfies Pick<SyncedPiniaRuntime, 'onLeadershipChange'>
+
 // NOTICE:
 // Vitest runs these store tests in Node, where localforage cannot select a
 // browser storage driver. The stage-model watcher legitimately asks the
@@ -96,6 +114,91 @@ vi.mock('vue-i18n', () => ({
 describe('airi-card store', () => {
   beforeEach(() => {
     setActivePinia(createPinia())
+    syncedRuntime.isLeader = false
+    syncedRuntime.leadershipListener = undefined
+    syncedRuntime.stopLeadershipListener.mockClear()
+  })
+
+  // ROOT CAUSE:
+  //
+  // A follower forwards its startup initialization to the current leader.
+  // The follower therefore has no local active-card watcher when it becomes
+  // the next leader.
+  //
+  // https://github.com/moeru-ai/airi/pull/2304
+  it('reinstalls the card watcher when a follower becomes the leader', async () => {
+    const stageModelStore = useSettingsStageModel()
+    const cardStore = useAiriCardStore()
+    await cardStore.initialize()
+
+    const vrmCardId = cardStore.addCard({
+      name: 'VRM card',
+      version: '1.0.0',
+      description: 'Card for the promoted leader.',
+      extensions: {
+        airi: {
+          modules: {
+            consciousness: { provider: 'mock-consciousness-provider', model: 'mock-consciousness-model' },
+            vision: { provider: 'mock-vision-provider', model: 'mock-vision-model' },
+            speech: { provider: 'mock-speech-provider', model: 'mock-speech-model', voice_id: 'mock-speech-voice' },
+            displayModelId: 'preset-vrm-1',
+          },
+          agents: {},
+        },
+      },
+    }, 'scratch')
+    const live2dCardId = cardStore.addCard({
+      name: 'Live2D card',
+      version: '1.0.0',
+      description: 'Card for the active leader.',
+      extensions: {
+        airi: {
+          modules: {
+            consciousness: { provider: 'mock-consciousness-provider', model: 'mock-consciousness-model' },
+            vision: { provider: 'mock-vision-provider', model: 'mock-vision-model' },
+            speech: { provider: 'mock-speech-provider', model: 'mock-speech-model', voice_id: 'mock-speech-voice' },
+            displayModelId: 'preset-live2d-1',
+          },
+          agents: {},
+        },
+      },
+    }, 'scratch')
+
+    stageModelStore.stageModelSelected = 'preset-live2d-1'
+    cardStore.startRuntime(syncedPinia)
+    cardStore.activeCardId = vrmCardId
+
+    expect(stageModelStore.stageModelSelected).toBe('preset-live2d-1')
+
+    syncedRuntime.leadershipListener?.(true)
+    expect(stageModelStore.stageModelSelected).toBe('preset-vrm-1')
+
+    cardStore.activeCardId = live2dCardId
+    expect(stageModelStore.stageModelSelected).toBe('preset-live2d-1')
+
+    syncedRuntime.leadershipListener?.(false)
+    cardStore.activeCardId = vrmCardId
+    expect(stageModelStore.stageModelSelected).toBe('preset-live2d-1')
+
+    cardStore.disposeRuntime()
+    expect(syncedRuntime.stopLeadershipListener).toHaveBeenCalledTimes(1)
+    expect(syncedRuntime.leadershipListener).toBeUndefined()
+  })
+
+  it('does not create runtime module stores for metadata-only consumers', () => {
+    const pinia = createPinia()
+    setActivePinia(pinia)
+
+    // ROOT CAUSE:
+    //
+    // The chat session store only reads the active card ID and system prompt,
+    // but creating the card store also created every runtime module store.
+    // The speech store then loaded provider voices in each auxiliary window.
+    useAiriCardStore(pinia)
+
+    expect(pinia.state.value.speech).toBeUndefined()
+    expect(pinia.state.value.consciousness).toBeUndefined()
+    expect(pinia.state.value.vision).toBeUndefined()
   })
 
   /**
diff --git a/packages/stage-ui/src/stores/modules/airi-card.ts b/packages/stage-ui/src/stores/modules/airi-card.ts
index 8b23439c6..76a71fd3c 100644
--- a/packages/stage-ui/src/stores/modules/airi-card.ts
+++ b/packages/stage-ui/src/stores/modules/airi-card.ts
@@ -1,10 +1,11 @@
 import type { Card, ccv3 } from '@proj-airi/ccc'
+import type { SyncedPiniaRuntime } from 'pinia-plugin-synced'
 
 import type { AiriCard, AiriExtension } from '../../types/airiCard'
 
 import { useLocalStorageManualReset } from '@proj-airi/stage-shared/composables'
 import { nanoid } from 'nanoid'
-import { defineStore, storeToRefs } from 'pinia'
+import { defineStore } from 'pinia'
 import { computed, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 
@@ -45,27 +46,15 @@ export const useAiriCardStore = defineStore('airi-card', () => {
 
   const activeCard = computed(() => cards.value.get(activeCardId.value))
 
-  const consciousnessStore = useConsciousnessStore()
-  const visionStore = useVisionStore()
-  const speechStore = useSpeechStore()
-  const artistryStore = useArtistryStore()
-  const stageModelStore = useSettingsStageModel()
-
-  const {
-    activeProvider: activeConsciousnessProvider,
-    activeModel: activeConsciousnessModel,
-  } = storeToRefs(consciousnessStore)
-
-  const {
-    activeProvider: activeVisionProvider,
-    activeModel: activeVisionModel,
-  } = storeToRefs(visionStore)
-
-  const {
-    activeSpeechProvider,
-    activeSpeechVoiceId,
-    activeSpeechModel,
-  } = storeToRefs(speechStore)
+  function useRuntimeModuleStores() {
+    return {
+      artistry: useArtistryStore(),
+      consciousness: useConsciousnessStore(),
+      speech: useSpeechStore(),
+      stageModel: useSettingsStageModel(),
+      vision: useVisionStore(),
+    }
+  }
 
   /**
    * `source` feeds the `card_created` analytics event: `scratch` = built in
@@ -162,6 +151,14 @@ export const useAiriCardStore = defineStore('airi-card', () => {
   }
 
   function resolveAiriExtension(card: Card | ccv3.CharacterCardV3): AiriExtension {
+    const {
+      artistry,
+      consciousness,
+      speech,
+      stageModel,
+      vision,
+    } = useRuntimeModuleStores()
+
     // Get existing extension if available
     const existingExtension = ('data' in card
       ? card.data?.extensions?.airi
@@ -170,27 +167,27 @@ export const useAiriCardStore = defineStore('airi-card', () => {
     // Create default modules config
     const defaultModules = {
       consciousness: {
-        provider: activeConsciousnessProvider.value,
-        model: activeConsciousnessModel.value,
+        provider: consciousness.activeProvider,
+        model: consciousness.activeModel,
       },
       vision: {
-        provider: activeVisionProvider.value,
-        model: activeVisionModel.value,
+        provider: vision.activeProvider,
+        model: vision.activeModel,
       },
       speech: {
-        provider: activeSpeechProvider.value,
-        model: activeSpeechModel.value,
-        voice_id: activeSpeechVoiceId.value,
+        provider: speech.activeSpeechProvider,
+        model: speech.activeSpeechModel,
+        voice_id: speech.activeSpeechVoiceId,
       },
-      displayModelId: stageModelStore.stageModelSelected,
+      displayModelId: stageModel.stageModelSelected,
       artistry: {
         enabled: false,
-        provider: artistryStore.globalProvider,
-        model: artistryStore.globalModel,
-        promptPrefix: artistryStore.globalPromptPrefix,
+        provider: artistry.globalProvider,
+        model: artistry.globalModel,
+        promptPrefix: artistry.globalPromptPrefix,
         widgetInstruction: DEFAULT_ARTISTRY_WIDGET_SPAWNING_PROMPT,
         spawnMode: 'bg_widget' as const,
-        options: artistryStore.globalProviderOptions,
+        options: artistry.globalProviderOptions,
         autonomousEnabled: false,
         autonomousThreshold: 70,
         autonomousTarget: 'assistant' as const,
@@ -295,7 +292,7 @@ export const useAiriCardStore = defineStore('airi-card', () => {
     }
   }
 
-  function initialize() {
+  async function initialize() {
     if (!cards.value.has('default')) {
       cards.value.set('default', newAiriCard({
         name: 'ReLU',
@@ -312,11 +309,19 @@ export const useAiriCardStore = defineStore('airi-card', () => {
     if (!cards.value.has(activeCardId.value))
       activeCardId.value = 'default'
 
-    applyActiveCardSettings()
+    initializeRuntimeModules()
   }
 
   function applyActiveCardSettings(newCard = activeCard.value) {
-    artistryStore.resetToGlobal()
+    const {
+      artistry,
+      consciousness,
+      speech,
+      stageModel,
+      vision,
+    } = useRuntimeModuleStores()
+
+    artistry.resetToGlobal()
 
     if (!newCard)
       return
@@ -326,41 +331,79 @@ export const useAiriCardStore = defineStore('airi-card', () => {
     if (!extension)
       return
 
-    activeConsciousnessProvider.value = extension?.modules?.consciousness?.provider
-    activeConsciousnessModel.value = extension?.modules?.consciousness?.model
+    consciousness.activeProvider = extension?.modules?.consciousness?.provider
+    consciousness.activeModel = extension?.modules?.consciousness?.model
 
-    activeVisionProvider.value = extension?.modules?.vision?.provider
-    activeVisionModel.value = extension?.modules?.vision?.model
+    vision.activeProvider = extension?.modules?.vision?.provider
+    vision.activeModel = extension?.modules?.vision?.model
 
-    activeSpeechProvider.value = extension?.modules?.speech?.provider
-    activeSpeechModel.value = extension?.modules?.speech?.model
-    activeSpeechVoiceId.value = extension?.modules?.speech?.voice_id
+    speech.activeSpeechProvider = extension?.modules?.speech?.provider
+    speech.activeSpeechModel = extension?.modules?.speech?.model
+    speech.activeSpeechVoiceId = extension?.modules?.speech?.voice_id
 
     // Apply body model if the card has a display model configured.
     // NOTICE: must set via store property directly (not storeToRefs .value) so Pinia's
     // proxy correctly calls the writable computed setter → stageModelSelectedState → updateStageModel().
     if (extension.modules?.displayModelId) {
-      stageModelStore.stageModelSelected = extension.modules.displayModelId
+      stageModel.stageModelSelected = extension.modules.displayModelId
     }
 
     if (extension.modules?.artistry) {
       if (extension.modules.artistry.provider)
-        artistryStore.activeProvider = extension.modules.artistry.provider
+        artistry.activeProvider = extension.modules.artistry.provider
       if (extension.modules.artistry.model)
-        artistryStore.activeModel = extension.modules.artistry.model
+        artistry.activeModel = extension.modules.artistry.model
       if (extension.modules.artistry.promptPrefix)
-        artistryStore.defaultPromptPrefix = extension.modules.artistry.promptPrefix
+        artistry.defaultPromptPrefix = extension.modules.artistry.promptPrefix
       if (extension.modules.artistry.options)
-        artistryStore.providerOptions = extension.modules.artistry.options
+        artistry.providerOptions = extension.modules.artistry.options
     }
   }
 
-  // Activation changes the stable card ID, while card editors replace the
-  // active card object without changing that ID. Observe both transitions so
-  // switching cards and saving edits to the current card apply consistently.
-  watch([activeCardId, activeCard], ([, newCard]) => {
-    applyActiveCardSettings(newCard)
-  }, { flush: 'sync', immediate: true })
+  let stopLeadershipListener: (() => void) | undefined
+  let stopRuntimeModuleWatcher: (() => void) | undefined
+
+  function initializeRuntimeModules() {
+    if (stopRuntimeModuleWatcher)
+      return
+
+    applyActiveCardSettings()
+
+    // Activation changes the stable card ID, while card editors replace the
+    // active card object without changing that ID. Only the Stage lifecycle
+    // owner applies those settings; metadata-only consumers stay lightweight.
+    stopRuntimeModuleWatcher = watch([activeCardId, activeCard], ([, newCard]) => {
+      applyActiveCardSettings(newCard)
+    }, { flush: 'sync' })
+  }
+
+  function stopRuntimeModules() {
+    stopRuntimeModuleWatcher?.()
+    stopRuntimeModuleWatcher = undefined
+  }
+
+  /**
+   * Keeps renderer-local card settings active only in the current leader.
+   * Repeated calls keep the first listener until {@link disposeRuntime} runs.
+   */
+  function startRuntime(syncedPinia: Pick<SyncedPiniaRuntime, 'onLeadershipChange'>) {
+    if (stopLeadershipListener)
+      return
+
+    stopLeadershipListener = syncedPinia.onLeadershipChange((isLeader) => {
+      if (isLeader)
+        initializeRuntimeModules()
+      else
+        stopRuntimeModules()
+    })
+  }
+
+  /** Stops renderer-local card settings and leadership tracking. */
+  function disposeRuntime() {
+    stopRuntimeModules()
+    stopLeadershipListener?.()
+    stopLeadershipListener = undefined
+  }
 
   function resetState() {
     // Clear card data before the selected ID. Otherwise the synchronous
@@ -384,26 +427,40 @@ export const useAiriCardStore = defineStore('airi-card', () => {
     getCard,
     resetState,
     initialize,
+    startRuntime,
+    disposeRuntime,
 
     currentModels: computed(() => {
+      const {
+        consciousness,
+        speech,
+        stageModel,
+        vision,
+      } = useRuntimeModuleStores()
+
       return {
         consciousness: {
-          provider: activeConsciousnessProvider.value,
-          model: activeConsciousnessModel.value,
+          provider: consciousness.activeProvider,
+          model: consciousness.activeModel,
         },
         vision: {
-          provider: activeVisionProvider.value,
-          model: activeVisionModel.value,
+          provider: vision.activeProvider,
+          model: vision.activeModel,
         },
         speech: {
-          provider: activeSpeechProvider.value,
-          model: activeSpeechModel.value,
-          voice_id: activeSpeechVoiceId.value,
+          provider: speech.activeSpeechProvider,
+          model: speech.activeSpeechModel,
+          voice_id: speech.activeSpeechVoiceId,
         },
-        displayModelId: stageModelStore.stageModelSelected,
+        displayModelId: stageModel.stageModelSelected,
         activeBackgroundId: activeCard.value?.extensions?.airi?.modules?.activeBackgroundId,
       } satisfies AiriExtension['modules']
     }),
     systemPrompt: computed(() => resolveSystemPrompt(activeCard.value)),
   }
+}, {
+  synced: {
+    actions: ['initialize'],
+    state: true,
+  },
 })
diff --git a/packages/stage-ui/src/stores/modules/artistry.ts b/packages/stage-ui/src/stores/modules/artistry.ts
index 43be6d45f..355b70d68 100644
--- a/packages/stage-ui/src/stores/modules/artistry.ts
+++ b/packages/stage-ui/src/stores/modules/artistry.ts
@@ -1,3 +1,5 @@
+import type {} from 'pinia-plugin-synced'
+
 import { useLocalStorageManualReset } from '@proj-airi/stage-shared/composables'
 import { defineStore } from 'pinia'
 import { computed, isRef, ref, watch } from 'vue'
@@ -184,6 +186,10 @@ export const useArtistryStore = defineStore('artistry', () => {
     resetToGlobal,
     resetState,
   }
+}, {
+  synced: {
+    state: true,
+  },
 })
 
 /**
diff --git a/packages/stage-ui/src/stores/modules/consciousness.ts b/packages/stage-ui/src/stores/modules/consciousness.ts
index c0ba9c194..124c0a4ba 100644
--- a/packages/stage-ui/src/stores/modules/consciousness.ts
+++ b/packages/stage-ui/src/stores/modules/consciousness.ts
@@ -1,3 +1,5 @@
+import type {} from 'pinia-plugin-synced'
+
 import { useLocalStorageManualReset } from '@proj-airi/stage-shared/composables'
 import { refManualReset } from '@vueuse/core'
 import { defineStore } from 'pinia'
@@ -117,4 +119,8 @@ export const useConsciousnessStore = defineStore('consciousness', () => {
     getModelsForProvider,
     resetState,
   }
+}, {
+  synced: {
+    state: true,
+  },
 })
diff --git a/packages/stage-ui/src/stores/modules/hearing.ts b/packages/stage-ui/src/stores/modules/hearing.ts
index a604c0460..0b638338c 100644
--- a/packages/stage-ui/src/stores/modules/hearing.ts
+++ b/packages/stage-ui/src/stores/modules/hearing.ts
@@ -2,6 +2,7 @@ import type { Span } from '@opentelemetry/api'
 import type { TranscriptionProviderWithExtraOptions } from '@xsai-ext/providers/utils'
 import type { WithUnknown } from '@xsai/shared'
 import type { StreamTranscriptionOptions as XSAIStreamTranscriptionOptions } from '@xsai/stream-transcription'
+import type {} from 'pinia-plugin-synced'
 
 import type { AIRIStreamTranscriptionResult } from '../../libs/providers/stream-transcription'
 import type { StreamingTranscriptionCallbacks, StreamingTranscriptionConsumer } from './streaming-transcription-consumers'
@@ -561,6 +562,10 @@ export const useHearingStore = defineStore('hearing-store', () => {
     getModelsForProvider,
     resetState,
   }
+}, {
+  synced: {
+    state: true,
+  },
 })
 
 export const useHearingSpeechInputPipeline = defineStore('modules:hearing:speech:audio-input-pipeline', () => {
diff --git a/packages/stage-ui/src/stores/modules/speech.ts b/packages/stage-ui/src/stores/modules/speech.ts
index c91b337eb..f4bbffa40 100644
--- a/packages/stage-ui/src/stores/modules/speech.ts
+++ b/packages/stage-ui/src/stores/modules/speech.ts
@@ -1,4 +1,5 @@
 import type { SpeechProviderWithExtraOptions } from '@xsai-ext/providers/utils'
+import type {} from 'pinia-plugin-synced'
 
 import type { VoiceInfo } from '../providers/provider'
 
@@ -7,7 +8,7 @@ import { useLocalStorageManualReset } from '@proj-airi/stage-shared/composables'
 import { refManualReset } from '@vueuse/core'
 import { generateSpeech } from '@xsai/generate-speech'
 import { defineStore, storeToRefs } from 'pinia'
-import { computed, onMounted, watch } from 'vue'
+import { computed, watch } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { toXml } from 'xast-util-to-xml'
 import { x } from 'xastscript'
@@ -242,15 +243,6 @@ export const useSpeechStore = defineStore('speech', () => {
     },
   )
 
-  onMounted(() => {
-    ensureActiveSpeechModel()
-    loadVoicesForProvider(activeSpeechProvider.value, activeSpeechModel.value || undefined).then(() => {
-      if (activeSpeechVoiceId.value) {
-        activeSpeechVoice.value = availableVoices.value[activeSpeechProvider.value]?.find(voice => voice.id === activeSpeechVoiceId.value)
-      }
-    })
-  })
-
   setupOfficialSpeechAutoPick({
     activeSpeechProvider,
     activeSpeechVoiceId,
@@ -469,4 +461,8 @@ export const useSpeechStore = defineStore('speech', () => {
     resolveSpeechInput,
     resetState,
   }
+}, {
+  synced: {
+    state: true,
+  },
 })
diff --git a/packages/stage-ui/src/stores/modules/vision/store.ts b/packages/stage-ui/src/stores/modules/vision/store.ts
index e0608508e..282f36808 100644
--- a/packages/stage-ui/src/stores/modules/vision/store.ts
+++ b/packages/stage-ui/src/stores/modules/vision/store.ts
@@ -1,3 +1,5 @@
+import type {} from 'pinia-plugin-synced'
+
 import { useLocalStorageManualReset } from '@proj-airi/stage-shared/composables'
 import { refManualReset } from '@vueuse/core'
 import { defineStore } from 'pinia'
@@ -86,4 +88,8 @@ export const useVisionStore = defineStore('vision', () => {
     getModelsForProvider,
     resetState,
   }
+}, {
+  synced: {
+    state: true,
+  },
 })
diff --git a/packages/stage-ui/src/stores/providers/provider.test.ts b/packages/stage-ui/src/stores/providers/provider.test.ts
index d383a38a6..69967cb3b 100644
--- a/packages/stage-ui/src/stores/providers/provider.test.ts
+++ b/packages/stage-ui/src/stores/providers/provider.test.ts
@@ -1,6 +1,7 @@
 import { createPinia, setActivePinia } from 'pinia'
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 
+import { OFFICIAL_SPEECH_PROVIDER_ID } from '../../libs/providers/providers/official'
 import { useProviderStore } from './provider'
 
 vi.mock('vue-i18n', () => ({
@@ -64,4 +65,38 @@ describe('provider store synchronization boundary', () => {
       expect.objectContaining({ id: 'auto' }),
     ])
   })
+
+  // ROOT CAUSE:
+  //
+  // Speech startup previously had both an immediate watcher and a mounted
+  // refresh. Multiple renderers could also request the same catalog through
+  // the synchronized provider action. Each caller created its own request.
+  //
+  // We keep one leader-owned request per provider, model, and configuration
+  // until it settles, so concurrent callers share the same result.
+  it('shares concurrent voice catalog requests', async () => {
+    const store = useProviderStore()
+    let resolveRequest: ((response: Response) => void) | undefined
+    const fetchMock = vi.fn(() => new Promise<Response>((resolve) => {
+      resolveRequest = resolve
+    }))
+    vi.stubGlobal('fetch', fetchMock)
+
+    try {
+      const first = store.listProviderVoices(OFFICIAL_SPEECH_PROVIDER_ID, 'auto')
+      const second = store.listProviderVoices(OFFICIAL_SPEECH_PROVIDER_ID, 'auto')
+
+      await vi.waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1))
+      resolveRequest?.(new Response(JSON.stringify({ voices: [], recommended: {} }), {
+        status: 200,
+        headers: { 'Content-Type': 'application/json' },
+      }))
+
+      await expect(Promise.all([first, second])).resolves.toEqual([[], []])
+      expect(fetchMock).toHaveBeenCalledTimes(1)
+    }
+    finally {
+      vi.unstubAllGlobals()
+    }
+  })
 })
diff --git a/packages/stage-ui/src/stores/providers/provider.ts b/packages/stage-ui/src/stores/providers/provider.ts
index 6a26613e0..eb18a1c3e 100644
--- a/packages/stage-ui/src/stores/providers/provider.ts
+++ b/packages/stage-ui/src/stores/providers/provider.ts
@@ -11,7 +11,7 @@ import type {
 import type {} from 'pinia-plugin-synced'
 
 import type { ProviderMetadata, ProviderValidationPlan } from '../../libs/providers'
-import type { ModelInfo, ProviderDefinition, ProviderInstance } from '../../libs/providers/types'
+import type { ModelInfo, ProviderDefinition, ProviderInstance, VoiceInfo } from '../../libs/providers/types'
 
 import { errorMessageFrom } from '@moeru/std'
 import { isCustomProvidersDisabled, isStageCapacitor, isStageTamagotchi } from '@proj-airi/stage-shared'
@@ -202,6 +202,7 @@ export const useProviderStore = defineStore('provider', () => {
     set: value => providerStateStore.runtime = value,
   })
   const providerValidationInFlight = new Map<string, Promise<boolean>>()
+  const providerVoiceListInFlight = new Map<string, Promise<VoiceInfo[]>>()
   const providerRevalidationLoops = new Map<string, { pause: () => void, resume: () => void }>()
 
   // Server-driven availability overrides for providers whose visibility can
@@ -610,13 +611,25 @@ export const useProviderStore = defineStore('provider', () => {
       return []
 
     const config = providerConfigStore.getProviderConfig(providerId) ?? {}
-    const provider = await definition.createProvider(config)
-    try {
-      return await listVoices(config, provider, model)
-    }
-    finally {
-      await disposeTemporaryProvider(provider)
-    }
+    const requestKey = JSON.stringify([providerId, model ?? null, config])
+    const pending = providerVoiceListInFlight.get(requestKey)
+    if (pending)
+      return pending
+
+    const task = (async () => {
+      const provider = await definition.createProvider(config)
+      try {
+        return await listVoices(config, provider, model)
+      }
+      finally {
+        await disposeTemporaryProvider(provider)
+      }
+    })()
+    providerVoiceListInFlight.set(requestKey, task)
+
+    return task.finally(() => {
+      providerVoiceListInFlight.delete(requestKey)
+    })
   }
 
   async function loadProviderModel(
diff --git a/packages/stage-ui/src/stores/settings/stage-model.ts b/packages/stage-ui/src/stores/settings/stage-model.ts
index 8e1f4691f..399f65fa9 100644
--- a/packages/stage-ui/src/stores/settings/stage-model.ts
+++ b/packages/stage-ui/src/stores/settings/stage-model.ts
@@ -1,8 +1,10 @@
+import type {} from 'pinia-plugin-synced'
+
 import type { DisplayModel } from '../display-models'
 
 import { useLocalStorageManualReset } from '@proj-airi/stage-shared/composables'
 import { refManualReset, useEventListener } from '@vueuse/core'
-import { defineStore } from 'pinia'
+import { defineStore, storeToRefs } from 'pinia'
 import { computed, watch } from 'vue'
 
 import { DisplayModelFormat, useDisplayModelsStore } from '../display-models'
@@ -10,13 +12,29 @@ import { DisplayModelFormat, useDisplayModelsStore } from '../display-models'
 export type StageModelRenderer = 'live2d' | 'vrm' | 'spine' | 'tachie' | 'mmd' | 'godot' | 'disabled' | undefined
 type BuiltInStageModelRenderer = Exclude<StageModelRenderer, 'godot'>
 
+const useStageModelSelectionStore = defineStore('settings-stage-model-selection', () => {
+  const selected = useLocalStorageManualReset<string>('settings/stage/model', 'preset-live2d-1')
+
+  function resetState() {
+    selected.reset()
+  }
+
+  return {
+    selected,
+    resetState,
+  }
+}, {
+  synced: {
+    state: true,
+  },
+})
+
 export const useSettingsStageModel = defineStore('settings-stage-model', () => {
   const displayModelsStore = useDisplayModelsStore()
+  const stageModelSelectionStore = useStageModelSelectionStore()
+  const { selected: stageModelSelectedState } = storeToRefs(stageModelSelectionStore)
   let stageModelUpdateSequence = 0
-  const stageModelStorageKey = 'settings/stage/model'
   const defaultStageModelId = 'preset-live2d-1'
-
-  const stageModelSelectedState = useLocalStorageManualReset<string>(stageModelStorageKey, defaultStageModelId)
   const stageModelSelected = computed<string>({
     get: () => stageModelSelectedState.value,
     set: (value) => {
@@ -142,7 +160,7 @@ export const useSettingsStageModel = defineStore('settings-stage-model', () => {
   async function resetState() {
     revokeStageModelUrl(stageModelSelectedUrl.value)
 
-    stageModelSelectedState.reset()
+    stageModelSelectionStore.resetState()
     stageModelSelectedDisplayModel.reset()
     stageModelSelectedUrl.reset()
     stageModelRenderer.reset()
diff --git a/patches/tab-election@4.6.2.patch b/patches/tab-election@4.6.2.patch
new file mode 100644
index 000000000..24c05aee7
--- /dev/null
+++ b/patches/tab-election@4.6.2.patch
@@ -0,0 +1,107 @@
+diff --git a/dist/tab.js b/dist/tab.js
+index 9fe1d1b6fe8b0172251ce7688f742bbb6c3b6da9..5dba20d6f551ec644eb168db95b45e48935879db 100644
+--- a/dist/tab.js
++++ b/dist/tab.js
+@@ -111,8 +111,8 @@ export class Tab extends EventTarget {
+                     // leader when it died — we are the leader now, so dispatch them to
+                     // ourselves (see the matching re-delivery for non-leader tabs in
+                     // `_onLeader`; the same at-least-once caveat applies).
+-                    this._callDeferreds.forEach(({ name, rest }, callNumber) => {
+-                        if (queued.has(`${this._id}:${callNumber}`))
++                    this._callDeferreds.forEach(({ awaitingLeader, name, rest }, callNumber) => {
++                        if (awaitingLeader || queued.has(`${this._id}:${callNumber}`))
+                             return;
+                         this._clearSentCall(callNumber);
+                         this._onCall(this._id, callNumber, name, ...rest);
+@@ -141,8 +141,12 @@ export class Tab extends EventTarget {
+                 this._clearSentCall(callNumber);
+                 reject(new Error('Call timed out'));
+             }, this._callTimeout);
+-            this._callDeferreds.set(callNumber, { resolve, reject, timeout, name, rest });
++            this._callDeferreds.set(callNumber, { awaitingLeader: true, resolve, reject, timeout, name, rest });
+             const hasLeader = await this.hasLeader();
++            const deferred = this._callDeferreds.get(callNumber);
++            if (!deferred)
++                return;
++            deferred.awaitingLeader = false;
+             try {
+                 if (this.isLeader && this._isLeaderReady) {
+                     this._onCall(this._id, callNumber, name, ...rest);
+@@ -294,8 +298,9 @@ export class Tab extends EventTarget {
+         if (this._sentCalls.get(callNumber))
+             this._callReceived(callNumber);
+         const deferred = this._callDeferreds.get(callNumber);
++        // Delivery is at-least-once, so a duplicate or late return can arrive after the call has already settled.
+         if (!deferred)
+-            return console.error('No deferred found for call', callNumber);
++            return;
+         clearTimeout(deferred.timeout);
+         this._callDeferreds.delete(callNumber);
+         if (error)
+@@ -345,8 +350,8 @@ export class Tab extends EventTarget {
+         // The same duplication happens inside a single election: a call queued while the leader was still initializing
+         // is dispatched by that leader AND re-sent from here, because the leader's `onLeader` broadcast goes out
+         // synchronously while the queued call's `onReturn` is still awaiting the handler.
+-        this._callDeferreds.forEach(({ name, rest }, callNumber) => {
+-            if (queued.has(`${this._id}:${callNumber}`) || this._sentCalls.has(callNumber))
++        this._callDeferreds.forEach(({ awaitingLeader, name, rest }, callNumber) => {
++            if (awaitingLeader || queued.has(`${this._id}:${callNumber}`) || this._sentCalls.has(callNumber))
+                 return;
+             try {
+                 this._sendCall(callNumber, name, rest);
+diff --git a/src/tab.ts b/src/tab.ts
+index 3d42674d6276ff707b890d8009d0af22298f00c3..57d4fa50d46a7e2195ea9e51de4586c90a62de2e 100644
+--- a/src/tab.ts
++++ b/src/tab.ts
+@@ -7,4 +7,6 @@ interface Deferred {
+ interface Deferred {
++  /** The original call is still waiting for `hasLeader()` to select its first delivery path. */
++  awaitingLeader: boolean;
+   resolve: (value: any) => void;
+   reject: (reason?: any) => void;
+   timeout: number;
+@@ -166,8 +168,8 @@ export class Tab<T = Record<string, any>> extends EventTarget implements Tab {
+           // leader when it died — we are the leader now, so dispatch them to
+           // ourselves (see the matching re-delivery for non-leader tabs in
+           // `_onLeader`; the same at-least-once caveat applies).
+-          this._callDeferreds.forEach(({ name, rest }, callNumber) => {
+-            if (queued.has(`${this._id}:${callNumber}`)) return;
++          this._callDeferreds.forEach(({ awaitingLeader, name, rest }, callNumber) => {
++            if (awaitingLeader || queued.has(`${this._id}:${callNumber}`)) return;
+             this._clearSentCall(callNumber);
+             this._onCall(this._id, callNumber, name, ...rest);
+           });
+@@ -194,8 +196,11 @@ export class Tab<T = Record<string, any>> extends EventTarget implements Tab {
+         this._clearSentCall(callNumber);
+         reject(new Error('Call timed out'));
+       }, this._callTimeout);
+-      this._callDeferreds.set(callNumber, { resolve, reject, timeout, name, rest });
++      this._callDeferreds.set(callNumber, { awaitingLeader: true, resolve, reject, timeout, name, rest });
+       const hasLeader = await this.hasLeader();
++      const deferred = this._callDeferreds.get(callNumber);
++      if (!deferred) return;
++      deferred.awaitingLeader = false;
+       try {
+         if (this.isLeader && this._isLeaderReady) {
+           this._onCall(this._id, callNumber, name, ...rest);
+@@ -337,7 +342,8 @@ export class Tab<T = Record<string, any>> extends EventTarget implements Tab {
+   _onReturn(callNumber: number, error: any, results: any) {
+     if (this._sentCalls.get(callNumber)) this._callReceived(callNumber);
+     const deferred = this._callDeferreds.get(callNumber);
+-    if (!deferred) return console.error('No deferred found for call', callNumber);
++    // Delivery is at-least-once, so a duplicate or late return can arrive after the call has already settled.
++    if (!deferred) return;
+     clearTimeout(deferred.timeout);
+     this._callDeferreds.delete(callNumber);
+     if (error) deferred.reject(error);
+@@ -386,8 +392,8 @@ export class Tab<T = Record<string, any>> extends EventTarget implements Tab {
+     // The same duplication happens inside a single election: a call queued while the leader was still initializing
+     // is dispatched by that leader AND re-sent from here, because the leader's `onLeader` broadcast goes out
+     // synchronously while the queued call's `onReturn` is still awaiting the handler.
+-    this._callDeferreds.forEach(({ name, rest }, callNumber) => {
+-      if (queued.has(`${this._id}:${callNumber}`) || this._sentCalls.has(callNumber)) return;
++    this._callDeferreds.forEach(({ awaitingLeader, name, rest }, callNumber) => {
++      if (awaitingLeader || queued.has(`${this._id}:${callNumber}`) || this._sentCalls.has(callNumber)) return;
+       try {
+         this._sendCall(callNumber, name, rest);
+       } catch (e) {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f526d1a27..aad7ea29a 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -1220,6 +1220,9 @@ patchedDependencies:
   sponsorkit@17.1.0:
     hash: f5887da52a29ae85732e01644d05c0c274231fe76b95aebeafbfab6dc4444f88
     path: patches/sponsorkit@17.1.0.patch
+  tab-election@4.6.2:
+    hash: ff8fe3c9aed66469fa00180f039fbf9f4f8e682430bfb3f6a07d9baf3f850674
+    path: patches/tab-election@4.6.2.patch
   uiohook-napi@1.5.5:
     hash: 012c5e5ad881d5ae40fc0af58832e31a0772ab0a74c038c8f4dfe51efaf398dd
     path: patches/uiohook-napi@1.5.5.patch
@@ -33029,7 +33032,7 @@ snapshots:
       '@moeru/std': 0.1.0-beta.20
       es-toolkit: 1.50.0
       pinia: 3.0.4(typescript@5.9.3)(vue@3.5.32(typescript@5.9.3))
-      tab-election: 4.6.2
+      tab-election: 4.6.2(patch_hash=ff8fe3c9aed66469fa00180f039fbf9f4f8e682430bfb3f6a07d9baf3f850674)
       vue: 3.5.32(typescript@5.9.3)
 
   pinia@3.0.4(typescript@5.9.3)(vue@3.5.32(typescript@5.9.3)):
@@ -34673,7 +34676,7 @@ snapshots:
     dependencies:
       '@pkgr/core': 0.2.9
 
-  tab-election@4.6.2: {}
+  tab-election@4.6.2(patch_hash=ff8fe3c9aed66469fa00180f039fbf9f4f8e682430bfb3f6a07d9baf3f850674): {}
 
   tabbable@6.4.0: {}
 
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
index 4edfe4bb2..ffff88f25 100644
--- a/pnpm-workspace.yaml
+++ b/pnpm-workspace.yaml
@@ -34,6 +34,7 @@ patchedDependencies:
   mineflayer-pathfinder: patches/mineflayer-pathfinder.patch
   pixi-live2d-display: patches/pixi-live2d-display.patch
   sponsorkit@17.1.0: patches/sponsorkit@17.1.0.patch
+  tab-election@4.6.2: patches/tab-election@4.6.2.patch
   uiohook-napi@1.5.5: patches/uiohook-napi@1.5.5.patch
 catalog:
   '@alexanderolsen/libsamplerate-js': ^2.1.2