fix(desktop): prevent macOS menu-bar artifacts on external displays

Electron was showing the main BrowserWindow before renderer load completed, so macOS could paint a blank window surface behind the menu bar. Persisted y=0 window state could also restore the titlebar under the menu-bar work area on external displays. Delay the initial show until the renderer entry is loaded, clamp restored macOS bounds into the display workArea, skip the macOS status-bar tray, and unhide the app before focusing restored windows.

Constraint: macOS external displays expose menu-bar and status-item chrome differently from Windows and Linux.
Rejected: Remove the native application menu | it would break expected macOS menu behavior without fixing the pre-load window surface.
Confidence: high
Scope-risk: narrow
Directive: Do not reintroduce pre-load main-window show without validating macOS external-display menu-bar rendering.
Tested: cd desktop && bun test electron/services/windows.test.ts electron/services/tray.test.ts electron/services/singleInstance.test.ts electron/services/menu.test.ts
Tested: bun run check:desktop
Tested: bun run check:native
Tested: git diff --check
Not-tested: Live dual-external-monitor screenshot smoke.

desktop/electron/main.ts

@@ -13,7 +13,7 @@ import {
 } from './services/notifications'
 import { installApplicationMenu } from './services/menu'
 import { acquireSingleInstanceLock } from './services/singleInstance'
-import { installTray, type TrayController } from './services/tray'
+import { installTray, shouldInstallTray, type TrayController } from './services/tray'
 import { ElectronUpdaterService } from './services/updater'
 import { createUpdateSmokeUpdaterFromEnv } from './services/updateSmoke'
 import { ElectronTerminalService, type TerminalSpawnInput } from './services/terminal'
@@ -161,7 +161,7 @@ function unsupported(name: string): never {
 }
 
 function emitNotificationAction(payload: unknown) {
-  showMainWindow(mainWindow)
+  showMainWindow(mainWindow, app)
   mainWindow?.webContents.send(ELECTRON_EVENT_CHANNELS.notificationAction, payload)
 }
 
@@ -314,8 +314,6 @@ async function createMainWindow() {
   })
 
   writeWindowSmokeSnapshot(mainWindow, 'after-create')
-  showMainWindow(mainWindow)
-  writeWindowSmokeSnapshot(mainWindow, 'after-initial-show')
 
   const entry = rendererEntry()
   if (/^https?:\/\//.test(entry)) {
@@ -325,7 +323,7 @@ async function createMainWindow() {
   }
 
   restoreWindowMaximized(mainWindow, restoredState)
-  showMainWindow(mainWindow)
+  showMainWindow(mainWindow, app)
   writeWindowSmokeSnapshot(mainWindow, 'after-final-show')
 }
 
@@ -341,18 +339,20 @@ app.whenReady().then(async () => {
     console.error('[desktop] failed to start Electron server sidecar', error)
   })
   await installApplicationMenu(app, () => mainWindow)
-  trayController = await installTray({
-    app,
-    desktopRoot: appRoot(),
-    show: () => showMainWindow(mainWindow),
-    quit: () => {
-      isQuitting = true
-      app.quit()
-    },
-  }).catch(error => {
-    console.error('[desktop] failed to create Electron tray', error)
-    return null
-  })
+  if (shouldInstallTray(process.platform)) {
+    trayController = await installTray({
+      app,
+      desktopRoot: appRoot(),
+      show: () => showMainWindow(mainWindow, app),
+      quit: () => {
+        isQuitting = true
+        app.quit()
+      },
+    }).catch(error => {
+      console.error('[desktop] failed to create Electron tray', error)
+      return null
+    })
+  }
   await createMainWindow()
   scheduleNotificationSmoke({
     env: process.env,
@@ -362,7 +362,7 @@ app.whenReady().then(async () => {
 
   app.on('activate', () => {
     if (mainWindow) {
-      showMainWindow(mainWindow)
+      showMainWindow(mainWindow, app)
       return
     }
     void createMainWindow()

desktop/electron/services/singleInstance.test.ts

@@ -30,13 +30,29 @@ describe('Electron single-instance service', () => {
   })
 
   it('registers a second-instance focus handler after acquiring the lock', () => {
+    let secondInstanceHandler: (() => void) | undefined
+    const window = {
+      isVisible: () => false,
+      isMinimized: () => false,
+      show: vi.fn(),
+      restore: vi.fn(),
+      focus: vi.fn(),
+    }
     const app = {
       requestSingleInstanceLock: vi.fn(() => true),
       quit: vi.fn(),
-      on: vi.fn(),
+      show: vi.fn(),
+      on: vi.fn((_event: string, handler: () => void) => {
+        secondInstanceHandler = handler
+      }),
     }
 
-    expect(acquireSingleInstanceLock(app as never, () => null)).toBe(true)
+    expect(acquireSingleInstanceLock(app as never, () => window as never)).toBe(true)
     expect(app.on).toHaveBeenCalledWith('second-instance', expect.any(Function))
+
+    secondInstanceHandler?.()
+    expect(app.show).toHaveBeenCalledTimes(1)
+    expect(window.show).toHaveBeenCalledTimes(1)
+    expect(window.focus).toHaveBeenCalledTimes(1)
   })
 })

desktop/electron/services/singleInstance.ts

@@ -17,7 +17,7 @@ export function acquireSingleInstanceLock(
   }
 
   app.on('second-instance', () => {
-    showMainWindow(getMainWindow())
+    showMainWindow(getMainWindow(), app)
   })
 
   return true

desktop/electron/services/tray.test.ts

@@ -2,7 +2,7 @@ import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs'
 import path from 'node:path'
 import { tmpdir } from 'node:os'
 import { afterEach, describe, expect, it, vi } from 'vitest'
-import { installTray, resolveTrayIconPath } from './tray'
+import { installTray, resolveTrayIconPath, shouldInstallTray } from './tray'
 
 const trayMocksKey = '__electronTrayMocks'
 
@@ -68,6 +68,12 @@ describe('Electron tray service', () => {
     }
   })
 
+  it('skips the status-bar tray on macOS and keeps it on Windows and Linux', () => {
+    expect(shouldInstallTray('darwin')).toBe(false)
+    expect(shouldInstallTray('win32')).toBe(true)
+    expect(shouldInstallTray('linux')).toBe(true)
+  })
+
   it('installs tray handlers that show the app, quit explicitly, and dispose cleanly', async () => {
     const root = mkdtempSync(path.join(tmpdir(), 'electron-tray-install-'))
     try {

desktop/electron/services/tray.ts

@@ -20,6 +20,10 @@ export function resolveTrayIconPath(desktopRoot: string): string {
   return resolved
 }
 
+export function shouldInstallTray(platform = process.platform): boolean {
+  return platform !== 'darwin'
+}
+
 export async function installTray({
   app,
   desktopRoot,

desktop/electron/services/windows.test.ts

@@ -3,6 +3,7 @@ import path from 'node:path'
 import { tmpdir } from 'node:os'
 import { describe, expect, it, vi } from 'vitest'
 import {
+  clampWindowStateToVisibleWorkArea,
   captureWindowState,
   hideWindowSafely,
   hasMeaningfulIntersection,
@@ -62,17 +63,44 @@ describe('Electron window service', () => {
         app as never,
         [{ bounds: { x: 0, y: 0, width: 1440, height: 900 }, workArea: { x: 0, y: 0, width: 1440, height: 860 } }],
         {},
+        'linux',
       )).toEqual(state)
       expect(readWindowState(
         app as never,
         [{ bounds: { x: 3000, y: 3000, width: 1440, height: 900 }, workArea: { x: 3000, y: 3000, width: 1440, height: 860 } }],
         {},
+        'linux',
       )).toBeNull()
     } finally {
       rmSync(tmp, { recursive: true, force: true })
     }
   })
 
+  it('clamps restored macOS windows below the menu bar work area', () => {
+    const tmp = mkdtempSync(path.join(tmpdir(), 'electron-window-state-clamp-'))
+    try {
+      const app = fakeApp(tmp)
+      const state = { x: 620, y: 0, width: 1280, height: 820, maximized: false }
+      const display = {
+        bounds: { x: 0, y: 0, width: 2560, height: 1440 },
+        workArea: { x: 0, y: 40, width: 2560, height: 1320 },
+      }
+      writeWindowState(app as never, state, {})
+
+      expect(clampWindowStateToVisibleWorkArea(state, [display])).toEqual({
+        ...state,
+        y: 40,
+      })
+      expect(readWindowState(app as never, [display], {}, 'darwin')).toEqual({
+        ...state,
+        y: 40,
+      })
+      expect(readWindowState(app as never, [display], {}, 'linux')).toEqual(state)
+    } finally {
+      rmSync(tmp, { recursive: true, force: true })
+    }
+  })
+
   it('does not capture minimized windows', () => {
     const window = {
       isMinimized: () => true,
@@ -106,9 +134,13 @@ describe('Electron window service', () => {
       restore: vi.fn(),
       focus: vi.fn(),
     }
+    const app = {
+      show: vi.fn(),
+    }
 
-    showMainWindow(window as never)
+    showMainWindow(window as never, app)
 
+    expect(app.show).toHaveBeenCalledTimes(1)
     expect(window.show).toHaveBeenCalledTimes(1)
     expect(window.restore).toHaveBeenCalledTimes(1)
     expect(window.focus).toHaveBeenCalledTimes(1)

desktop/electron/services/windows.ts

@@ -58,10 +58,35 @@ export function isWindowStateVisibleOnAnyDisplay(
   )
 }
 
+function clamp(value: number, min: number, max: number): number {
+  return Math.min(Math.max(value, min), max)
+}
+
+export function clampWindowStateToVisibleWorkArea(
+  state: StoredWindowState,
+  displays: Array<Pick<Display, 'bounds' | 'workArea'>>,
+): StoredWindowState {
+  const display = displays.find(candidate =>
+    hasMeaningfulIntersection(state, candidate.workArea ?? candidate.bounds),
+  )
+  if (!display) return state
+
+  const workArea = display.workArea ?? display.bounds
+  const maxX = workArea.x + Math.max(0, workArea.width - state.width)
+  const maxY = workArea.y + Math.max(0, workArea.height - state.height)
+
+  return {
+    ...state,
+    x: clamp(state.x, workArea.x, maxX),
+    y: clamp(state.y, workArea.y, maxY),
+  }
+}
+
 export function readWindowState(
   app: App,
   displays: Array<Pick<Display, 'bounds' | 'workArea'>>,
   env: NodeJS.ProcessEnv = process.env,
+  platform = process.platform,
 ): StoredWindowState | null {
   const statePath = windowStatePath(app, env)
   if (!existsSync(statePath)) return null
@@ -70,7 +95,9 @@ export function readWindowState(
     const parsed = JSON.parse(readFileSync(statePath, 'utf-8')) as StoredWindowState
     if (!isPersistableWindowState(parsed)) return null
     if (!isWindowStateVisibleOnAnyDisplay(parsed, displays)) return null
-    return parsed
+    return platform === 'darwin'
+      ? clampWindowStateToVisibleWorkArea(parsed, displays)
+      : parsed
   } catch (error) {
     console.error(`[desktop] failed to read Electron window state ${statePath}:`, error)
     return null
@@ -147,8 +174,13 @@ export function toggleWindowFullScreen(window: BrowserWindow, platform = process
   window.setFullScreen(!window.isFullScreen())
 }
 
-export function showMainWindow(window: BrowserWindow | null) {
+type MacOsWindowVisibilityApp = {
+  show?: () => void
+}
+
+export function showMainWindow(window: BrowserWindow | null, app?: MacOsWindowVisibilityApp) {
   if (!window) return
+  app?.show?.()
   if (!window.isVisible()) window.show()
   if (window.isMinimized()) window.restore()
   window.focus()