feat(desktop): notify renderer when GPU acceleration is disabled due to remote display

Remote displays (RDP/SSH/X11) silently disable GPU hardware acceleration with
only a console.log, leaving the user unaware that software rendering is
active. Expose the detected reason over IPC and surface a dismissible banner
in the renderer.

apps/desktop/electron/main.cjs

@@ -150,6 +150,8 @@ if (REMOTE_DISPLAY_REASON) {
   )
 }
 
+ipcMain.handle('hermes:get-remote-display-reason', () => REMOTE_DISPLAY_REASON)
+
 // Keep the renderer running at full speed while the window is in the background
 // or occluded. The chat transcript streams to screen through a
 // requestAnimationFrame-gated flush; Chromium pauses rAF (and clamps timers)

apps/desktop/electron/preload.cjs

@@ -140,6 +140,7 @@ contextBridge.exposeInMainWorld('hermesDesktop', {
     return () => ipcRenderer.removeListener('hermes:bootstrap:event', listener)
   },
   getVersion: () => ipcRenderer.invoke('hermes:version'),
+  getRemoteDisplayReason: () => ipcRenderer.invoke('hermes:get-remote-display-reason'),
   uninstall: {
     summary: () => ipcRenderer.invoke('hermes:uninstall:summary'),
     run: mode => ipcRenderer.invoke('hermes:uninstall:run', { mode })

apps/desktop/src/app/desktop-controller.tsx

@@ -8,6 +8,7 @@ import { DesktopInstallOverlay } from '@/components/desktop-install-overlay'
 import { DesktopOnboardingOverlay } from '@/components/desktop-onboarding-overlay'
 import { GatewayConnectingOverlay } from '@/components/gateway-connecting-overlay'
 import { Pane, PaneMain } from '@/components/pane-shell'
+import { RemoteDisplayBanner } from '@/components/remote-display-banner'
 import { useMediaQuery } from '@/hooks/use-media-query'
 import { useSkinCommand } from '@/themes/use-skin-command'
 
@@ -956,6 +957,7 @@ export function DesktopController() {
 
   const overlays = (
     <>
+      <RemoteDisplayBanner />
       {!isSecondaryWindow() && <DesktopInstallOverlay />}
       {!isSecondaryWindow() && (
         <DesktopOnboardingOverlay

apps/desktop/src/components/remote-display-banner.tsx

@@ -0,0 +1,42 @@
+import { useEffect, useState } from 'react'
+
+import { Alert, AlertDescription } from '@/components/ui/alert'
+import { Button } from '@/components/ui/button'
+import { Codicon } from '@/components/ui/codicon'
+import { useI18n } from '@/i18n'
+import { Info } from '@/lib/icons'
+
+export function RemoteDisplayBanner() {
+  const { t } = useI18n()
+  const [reason, setReason] = useState<string | null>(null)
+  const [dismissed, setDismissed] = useState(false)
+
+  useEffect(() => {
+    void window.hermesDesktop?.getRemoteDisplayReason?.().then(result => setReason(result))
+  }, [])
+
+  if (!reason || dismissed) {
+    return null
+  }
+
+  return (
+    <div className="pointer-events-none fixed left-1/2 top-[calc(var(--titlebar-height,34px)+0.75rem)] z-[200] w-[min(32rem,calc(100%-2rem))] -translate-x-1/2">
+      <Alert className="pointer-events-auto grid-cols-[auto_minmax(0,1fr)_auto] border-(--stroke-nous) bg-popover/95 pr-2.5 shadow-nous backdrop-blur-md">
+        <Info className="text-muted-foreground" />
+        <AlertDescription className="col-start-2">
+          <p className="m-0">{t.remoteDisplayBanner.message(reason)}</p>
+        </AlertDescription>
+        <Button
+          aria-label={t.remoteDisplayBanner.dismiss}
+          className="col-start-3 -mr-1 text-muted-foreground"
+          onClick={() => setDismissed(true)}
+          size="icon-xs"
+          type="button"
+          variant="ghost"
+        >
+          <Codicon name="close" size="0.875rem" />
+        </Button>
+      </Alert>
+    </div>
+  )
+}

apps/desktop/src/global.d.ts

@@ -102,6 +102,7 @@ declare global {
       cancelBootstrap: () => Promise<{ ok: boolean; cancelled: boolean }>
       onBootstrapEvent: (callback: (payload: DesktopBootstrapEvent) => void) => () => void
       getVersion: () => Promise<DesktopVersionInfo>
+      getRemoteDisplayReason?: () => Promise<string | null>
       updates: {
         check: () => Promise<DesktopUpdateStatus>
         apply: (opts?: DesktopUpdateApplyOptions) => Promise<DesktopUpdateApplyResult>

apps/desktop/src/i18n/en.ts

@@ -146,6 +146,12 @@ export const en: Translations = {
     }
   },
 
+  remoteDisplayBanner: {
+    message: reason =>
+      `Software rendering active — remote display detected (${reason}). GPU acceleration is disabled to prevent flickering.`,
+    dismiss: 'Dismiss'
+  },
+
   titlebar: {
     hideSidebar: 'Hide sidebar',
     showSidebar: 'Show sidebar',

apps/desktop/src/i18n/ja.ts

@@ -147,6 +147,12 @@ export const ja = defineLocale({
     }
   },
 
+  remoteDisplayBanner: {
+    message: reason =>
+      `ソフトウェアレンダリングが有効です — リモートディスプレイを検出しました（${reason}）。ちらつきを防ぐため GPU アクセラレーションは無効化されています。`,
+    dismiss: '閉じる'
+  },
+
   titlebar: {
     hideSidebar: 'サイドバーを非表示',
     showSidebar: 'サイドバーを表示',

apps/desktop/src/i18n/types.ts

@@ -159,6 +159,11 @@ export interface Translations {
     }
   }
 
+  remoteDisplayBanner: {
+    message: (reason: string) => string
+    dismiss: string
+  }
+
   titlebar: {
     hideSidebar: string
     showSidebar: string

apps/desktop/src/i18n/zh-hant.ts

@@ -142,6 +142,11 @@ export const zhHant = defineLocale({
     }
   },
 
+  remoteDisplayBanner: {
+    message: reason => `軟體繪圖已啟用 — 偵測到遠端顯示（${reason}）。為防止畫面閃爍，已停用 GPU 加速。`,
+    dismiss: '關閉'
+  },
+
   titlebar: {
     hideSidebar: '隱藏側邊欄',
     showSidebar: '顯示側邊欄',

apps/desktop/src/i18n/zh.ts

@@ -142,6 +142,11 @@ export const zh: Translations = {
     }
   },
 
+  remoteDisplayBanner: {
+    message: reason => `软件渲染已启用 — 检测到远程显示（${reason}）。为防止画面闪烁，已禁用 GPU 加速。`,
+    dismiss: '关闭'
+  },
+
   titlebar: {
     hideSidebar: '隐藏侧边栏',
     showSidebar: '显示侧边栏',