fix: keep macOS artifact preview panel clickable above drag region (#1067)

src/components/file-preview/ArtifactPanel.tsx

@@ -17,11 +17,11 @@
  * toolbar buttons, "View file changes →" links) can drive it.
  */
 import { useLayoutEffect, useMemo, useRef } from 'react';
+import { cn } from '@/lib/utils';
 import { Eye, FileEdit, FolderOpen, FolderTree, X } from 'lucide-react';
 import { useTranslation } from 'react-i18next';
 import { toast } from 'sonner';
 import { Button } from '@/components/ui/button';
-import { cn } from '@/lib/utils';
 import { supportsRichDocumentPreview, type GeneratedFile } from '@/lib/generated-files';
 import { invokeIpc } from '@/lib/api-client';
 import type { AgentSummary } from '@/types/agent';
@@ -44,6 +44,7 @@ export interface ArtifactPanelProps {
 
 export function ArtifactPanel({ files, agent, runStartedAt, refreshSignal }: ArtifactPanelProps) {
   const { t } = useTranslation('chat');
+  const isMac = window.electron?.platform === 'darwin';
   const tab = useArtifactPanel((s) => s.tab);
   const setTab = useArtifactPanel((s) => s.setTab);
   const focusedFile = useArtifactPanel((s) => s.focusedFile);
@@ -61,9 +62,16 @@ export function ArtifactPanel({ files, agent, runStartedAt, refreshSignal }: Art
   };
 
   return (
-    <div data-testid="artifact-panel" className="flex h-full min-h-0 flex-col bg-background">
+    <div data-testid="artifact-panel" className={cn('flex h-full min-h-0 flex-col bg-background', isMac && 'no-drag')}>
       <div className="relative z-30 flex shrink-0 items-center justify-between gap-2 border-b border-black/5 bg-background px-3 py-2 dark:border-white/10">
-        <div className="flex min-w-0 items-center gap-1">
+        {isMac && (
+          <div
+            data-testid="artifact-panel-drag-region"
+            className="drag-region absolute inset-0 z-0"
+            aria-hidden="true"
+          />
+        )}
+        <div className={cn('flex min-w-0 items-center gap-1', isMac && 'no-drag relative z-10')}>
           {richFocusedFile ? (
             <PanelTabButton
               testId="artifact-panel-action-open-folder"
@@ -102,7 +110,7 @@ export function ArtifactPanel({ files, agent, runStartedAt, refreshSignal }: Art
           type="button"
           variant="ghost"
           size="icon"
-          className="h-7 w-7 shrink-0"
+          className={cn('h-7 w-7 shrink-0', isMac && 'no-drag relative z-10')}
           onClick={close}
           aria-label={t('filePreview.actions.close', 'Close')}
         >
@@ -110,7 +118,7 @@ export function ArtifactPanel({ files, agent, runStartedAt, refreshSignal }: Art
         </Button>
       </div>
 
-      <div className="relative z-0 min-h-0 flex-1 overflow-hidden">
+      <div className={cn('relative z-0 min-h-0 flex-1 overflow-hidden', isMac && 'no-drag')}>
         <div className={cn('h-full min-h-0', visibleTab !== 'changes' && 'hidden')}>
           <ChangesTab
             files={files}

src/pages/Chat/index.tsx

@@ -768,7 +768,10 @@ export function Chat() {
       className={cn(
         'relative flex min-h-0 -m-6 overflow-hidden transition-colors duration-500',
         'bg-background',
-        isMac && 'rounded-tl-2xl shadow-[inset_1px_1px_0_hsl(var(--border)/0.55)]',
+        // Stack above MainLayout's mac-main-drag-region (z-10) so the right-hand
+        // artifact/preview pane stays clickable; window drag is handled by the
+        // sidebar + chat-toolbar drag strips instead.
+        isMac && 'z-20 rounded-tl-2xl shadow-[inset_1px_1px_0_hsl(var(--border)/0.55)]',
         isWindows && 'rounded-tl-2xl',
       )}
       style={{ height: isMac ? '100vh' : 'calc(100vh - 2.5rem)' }}
@@ -1022,7 +1025,11 @@ export function Chat() {
             <PanelResizeDividerLazy containerRef={splitContainerRef} />
           </Suspense>
           <aside
-            className="relative z-20 hidden shrink-0 border-l border-black/5 dark:border-white/10 lg:flex lg:flex-col"
+            data-testid="artifact-panel-aside"
+            className={cn(
+              'relative z-20 hidden shrink-0 border-l border-black/5 dark:border-white/10 lg:flex lg:flex-col',
+              isMac && 'no-drag',
+            )}
             style={{ width: `${panelWidthPct}%` }}
           >
             <Suspense

tests/e2e/mac-titlebar-drag-region.spec.ts

@@ -3,7 +3,7 @@ import { expect, test } from './fixtures/electron';
 test.describe('macOS frameless chrome', () => {
   test.skip(process.platform !== 'darwin', 'macOS drag-region chrome only');
 
-  test('keeps a draggable strip above the right content pane', async ({ page }) => {
+  test('keeps a draggable strip above non-chat pages and stacks chat above it', async ({ page }) => {
     await expect(page.getByTestId('setup-page')).toBeVisible();
     await page.getByTestId('setup-skip-button').click();
 
@@ -18,5 +18,9 @@ test.describe('macOS frameless chrome', () => {
     expect(box).not.toBeNull();
     expect(box!.width).toBeGreaterThan(200);
     expect(box!.height).toBeGreaterThanOrEqual(24);
+
+    const chatPage = page.getByTestId('chat-page');
+    await expect(chatPage).toBeVisible();
+    await expect(chatPage).toHaveCSS('z-index', '20');
   });
 });

tests/unit/artifact-panel.test.tsx

@@ -140,4 +140,32 @@ describe('ArtifactPanel', () => {
     fireEvent.pointerDown(changesButton, { button: 0 });
     expect(screen.getAllByTestId('file-preview-body')[0]).toHaveTextContent('diff');
   });
+
+  it('marks macOS chrome so preview tabs and content stay clickable', () => {
+    window.electron.platform = 'darwin';
+
+    useArtifactPanel.setState({
+      open: true,
+      tab: 'preview',
+      focusedFile: {
+        filePath: '/tmp/demo.md',
+        fileName: 'demo.md',
+        ext: '.md',
+        mimeType: 'text/markdown',
+        contentType: 'document',
+      },
+      widthPct: ARTIFACT_PANEL_DEFAULT_WIDTH,
+    });
+
+    render(
+      <ArtifactPanel
+        files={[makeGeneratedFile()]}
+        agent={null}
+      />,
+    );
+
+    expect(screen.getByTestId('artifact-panel')).toHaveClass('no-drag');
+    expect(screen.getByTestId('artifact-panel-drag-region')).toHaveClass('drag-region');
+    expect(screen.getByTestId('artifact-panel-tab-preview').parentElement).toHaveClass('no-drag');
+  });
 });

tests/unit/chat-artifact-panel-layout.test.tsx

@@ -102,6 +102,15 @@ describe('Chat artifact panel layout', () => {
     expect(actions).toHaveClass('no-drag');
   });
 
+  it('stacks the chat page above the macOS main drag strip', async () => {
+    window.electron.platform = 'darwin';
+
+    render(<Chat />);
+
+    const chatPage = await screen.findByTestId('chat-page');
+    expect(chatPage).toHaveClass('z-20');
+  });
+
   it('layers the right artifact panel above the macOS drag strip', async () => {
     window.electron.platform = 'darwin';
 
@@ -112,5 +121,6 @@ describe('Chat artifact panel layout', () => {
 
     expect(aside).toHaveClass('relative');
     expect(aside).toHaveClass('z-20');
+    expect(aside).toHaveClass('no-drag');
   });
 });