fix(ohos): preserve native window controls

src/web-ui/src/app/components/NavPanel/components/PersistentFooterActions.tsx

@@ -25,7 +25,6 @@ import { useToolbarModeContext } from '@/flow_chat/components/toolbar-mode/Toolb
 import { useNotification } from '@/shared/notification-system';
 import { useAccountLoginState } from '@/infrastructure/account/useAccountLoginState';
 import NotificationButton from '../../TitleBar/NotificationButton';
-import GithubStarButton from './GithubStarButton';
 import { usePrivacy } from '../../Privacy/PrivacyContext';
 import {
   hasActionableUnreadReply,
@@ -425,7 +424,6 @@ const PersistentFooterActions: React.FC = () => {
         </div>
 
         <div className="bitfun-nav-panel__footer-right">
-          <GithubStarButton />
           <NotificationButton className="bitfun-nav-panel__footer-btn" navFooterHoverIconSwap />
         </div>
       </div>

src/web-ui/src/app/components/SceneBar/SceneBar.tsx

@@ -27,6 +27,7 @@ interface SceneBarProps {
   onMaximize?: () => void;
   onClose?: () => void;
   isMaximized?: boolean;
+  reserveNativeWindowControls?: boolean;
 }
 
 const SceneBar: React.FC<SceneBarProps> = ({
@@ -35,12 +36,14 @@ const SceneBar: React.FC<SceneBarProps> = ({
   onMaximize,
   onClose,
   isMaximized = false,
+  reserveNativeWindowControls = false,
 }) => {
   const { openTabs, activeTabId, tabDefs, activateScene, closeScene } = useSceneManager();
   const sessionTitle = useCurrentSessionTitle();
   const settingsTabTitle = useCurrentSettingsTabTitle();
   const { t } = useI18n('common');
   const hasWindowControls = !!(onMinimize && onMaximize && onClose);
+  const showWindowControls = hasWindowControls || reserveNativeWindowControls;
   const sceneBarClassName = `bitfun-scene-bar ${!hasWindowControls ? 'bitfun-scene-bar--no-controls' : ''} ${className}`.trim();
   const isSingleTab = openTabs.length <= 1;
   const tabCount = Math.max(openTabs.length, 1);
@@ -108,13 +111,14 @@ const SceneBar: React.FC<SceneBarProps> = ({
         })}
       </div>
 
-      {hasWindowControls && (
+      {showWindowControls && (
         <div className="bitfun-scene-bar__controls" data-bf-component="scene-bar" data-bf-part="controls">
           <WindowControls
-            onMinimize={onMinimize!}
-            onMaximize={onMaximize!}
-            onClose={onClose!}
+            onMinimize={onMinimize}
+            onMaximize={onMaximize}
+            onClose={onClose}
             isMaximized={isMaximized}
+            nativePlaceholder={reserveNativeWindowControls && !hasWindowControls}
           />
         </div>
       )}

src/web-ui/src/app/layout/AppLayout.tsx

@@ -34,7 +34,7 @@ import { WorkspaceKind } from '@/shared/types';
 import { SSHContext } from '@/features/ssh-remote/SSHRemoteContext';
 import { shortcutManager, parseStoredKeybindings } from '@/infrastructure/services/ShortcutManager';
 import { useSessionModeStore } from '../stores/sessionModeStore';
-import { isMacOSDesktopRuntime } from '@/infrastructure/runtime';
+import { isMacOSDesktopRuntime, isOpenHarmonyRuntime } from '@/infrastructure/runtime';
 import { flowChatSessionConfigForWorkspace } from '../utils/projectSessionWorkspace';
 import { notificationService } from '@/shared/notification-system';
 import { AppearanceBackgroundMediaLayer, appearanceRuntime, useAppearance } from '@/infrastructure/appearance';
@@ -83,6 +83,7 @@ const AppLayout: React.FC<AppLayoutProps> = ({ className = '' }) => {
   const { t: tCommon } = useI18n('common');
   const currentAppearance = useAppearance().current;
   const backgroundMedia = currentAppearance?.backgroundMedia;
+  const isOpenHarmony = isOpenHarmonyRuntime();
   usePermissionRequestNotify();
   const {
     currentWorkspace,
@@ -757,10 +758,11 @@ const AppLayout: React.FC<AppLayoutProps> = ({ className = '' }) => {
         {/* Main content — always render WorkspaceBody; WelcomeScene in viewport handles no-workspace state */}
         <main className="bitfun-app-main-workspace" data-testid="app-main-content" data-bf-component="app-layout" data-bf-part="main">
           <WorkspaceBody
-            onMinimize={canUseNativeWindowControls && !isMacOS ? handleMinimize : undefined}
-            onMaximize={canUseNativeWindowControls ? handleMaximize : undefined}
-            onClose={canUseNativeWindowControls && !isMacOS ? handleClose : undefined}
+            onMinimize={canUseNativeWindowControls && !isMacOS && !isOpenHarmony ? handleMinimize : undefined}
+            onMaximize={canUseNativeWindowControls && !isOpenHarmony ? handleMaximize : undefined}
+            onClose={canUseNativeWindowControls && !isMacOS && !isOpenHarmony ? handleClose : undefined}
             isMaximized={isMaximized}
+            reserveNativeWindowControls={isOpenHarmony}
             isEntering={transitionDir === 'entering'}
             isExiting={transitionDir === 'returning'}
           />

src/web-ui/src/app/layout/WorkspaceBody.tsx

@@ -32,6 +32,7 @@ interface WorkspaceBodyProps {
   onMaximize?: () => void;
   onClose?: () => void;
   isMaximized?: boolean;
+  reserveNativeWindowControls?: boolean;
   sceneOverlay?: React.ReactNode;
 }
 
@@ -43,6 +44,7 @@ const WorkspaceBody: React.FC<WorkspaceBodyProps> = ({
   onMaximize,
   onClose,
   isMaximized = false,
+  reserveNativeWindowControls = false,
   sceneOverlay,
 }) => {
   const { workspace: currentWorkspace } = useCurrentWorkspace();
@@ -177,6 +179,7 @@ const WorkspaceBody: React.FC<WorkspaceBodyProps> = ({
           onMaximize={onMaximize}
           onClose={onClose}
           isMaximized={isMaximized}
+          reserveNativeWindowControls={reserveNativeWindowControls}
         />
         <SceneViewport
           workspacePath={currentWorkspace?.rootPath}

src/web-ui/src/component-library/components/WindowControls/WindowControls.tsx

@@ -23,6 +23,8 @@ export interface WindowControlsProps extends React.HTMLAttributes<HTMLDivElement
   'data-testid-minimize'?: string;
   'data-testid-maximize'?: string;
   'data-testid-close'?: string;
+  /** Render only the native-titlebar spacer used by the OHOS host. */
+  nativePlaceholder?: boolean;
 }
 
 /**
@@ -46,9 +48,15 @@ export const WindowControls: React.FC<WindowControlsProps> = ({
   'data-testid-minimize': testIdMinimize,
   'data-testid-maximize': testIdMaximize,
   'data-testid-close': testIdClose,
+  nativePlaceholder = false,
   ...props
 }) => {
   const { t } = useTranslation('common');
+
+  if (nativePlaceholder) {
+    return <div className={`window-controls ${className}`} style={{ width: 128 }} {...props} />;
+  }
+
   const defaultMinimizeIcon = (
     <svg width="10" height="10" viewBox="0 0 14 14" fill="none">
       <line x1="3" y1="7" x2="11" y2="7" stroke="currentColor" strokeWidth="1.5" strokeLinecap="round"/>

src/web-ui/src/infrastructure/runtime/environment.test.ts

@@ -1,6 +1,6 @@
 import { afterEach, describe, expect, it, vi } from 'vitest';
 
-import { isTauriRuntime, supportsNativeWindowControls } from './environment';
+import { isOpenHarmonyRuntime, isTauriRuntime, supportsNativeWindowControls } from './environment';
 
 const setTauriInternals = (value: unknown) => {
   vi.stubGlobal('window', {
@@ -40,4 +40,13 @@ describe('runtime environment', () => {
     expect(isTauriRuntime()).toBe(true);
     expect(supportsNativeWindowControls()).toBe(true);
   });
+
+  it('recognizes the OpenHarmony webview runtime', () => {
+    vi.stubGlobal('navigator', {
+      userAgent: 'Mozilla/5.0 OpenHarmony 5.0',
+      platform: 'OpenHarmony',
+    });
+
+    expect(isOpenHarmonyRuntime()).toBe(true);
+  });
 });

src/web-ui/src/infrastructure/runtime/environment.ts

@@ -23,6 +23,17 @@ export const supportsNativeWindowControls = (): boolean => {
   return isTauriRuntime() && typeof currentWindow?.label === 'string';
 };
 
+/**
+ * OpenHarmony renders the window chrome in its native ArkUI host.  The web
+ * view must reserve that space but must not render a second set of buttons or
+ * call the desktop/Tauri window APIs for the same action.
+ */
+export const isOpenHarmonyRuntime = (): boolean => {
+  if (typeof navigator === 'undefined') return false;
+  const fingerprint = `${navigator.userAgent ?? ''} ${navigator.platform ?? ''}`;
+  return /(?:openharmony|harmonyos|ohos)/i.test(fingerprint);
+};
+
 export const supportsNativeWindowDragging = supportsNativeWindowControls;
 
 export const isMacOSDesktopRuntime = (): boolean =>