From fc53f978b665d689e5ef10da57bbcdeb29f2c3d6 Mon Sep 17 00:00:00 2001
From: Pim de Jong <22365764+P-de-Jong@users.noreply.github.com>
Date: Sun, 12 Apr 2026 10:18:41 +0200
Subject: [PATCH] [codex] Guard traffic light sync off macOS (#531)

---
 src/main/window/createMainWindow.test.ts | 51 ++++++++++++++++++++++++
 src/main/window/createMainWindow.ts      |  2 +-
 src/renderer/src/lib/ui-zoom.ts          | 10 ++++-
 3 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/src/main/window/createMainWindow.test.ts b/src/main/window/createMainWindow.test.ts
index 811b68983be..48092db7a47 100644
--- a/src/main/window/createMainWindow.test.ts
+++ b/src/main/window/createMainWindow.test.ts
@@ -34,6 +34,7 @@ vi.mock('../browser/browser-manager', () => ({
 }))
 
 import { createMainWindow } from './createMainWindow'
+import { ipcMain } from 'electron'
 
 describe('createMainWindow', () => {
   beforeEach(() => {
@@ -41,6 +42,8 @@ describe('createMainWindow', () => {
     openExternalMock.mockReset()
     attachGuestPoliciesMock.mockReset()
     isMock.dev = false
+    vi.mocked(ipcMain.on).mockReset()
+    vi.mocked(ipcMain.removeListener).mockReset()
   })
 
   it('enables renderer sandboxing and opens external links safely', () => {
@@ -436,4 +439,52 @@ describe('createMainWindow', () => {
     windowHandlers['will-prevent-unload']()
     expect(onQuitAborted).toHaveBeenCalledTimes(1)
   })
+
+  it('ignores traffic light sync IPC on non-macOS', () => {
+    const windowHandlers: Record<string, (...args: any[]) => void> = {}
+    const webContents = {
+      on: vi.fn((event, handler) => {
+        windowHandlers[event] = handler
+      }),
+      setZoomLevel: vi.fn(),
+      setBackgroundThrottling: vi.fn(),
+      invalidate: vi.fn(),
+      setWindowOpenHandler: vi.fn(),
+      send: vi.fn()
+    }
+    const browserWindowInstance = {
+      webContents,
+      on: vi.fn(),
+      isDestroyed: vi.fn(() => false),
+      isMaximized: vi.fn(() => true),
+      isFullScreen: vi.fn(() => false),
+      getSize: vi.fn(() => [1200, 800]),
+      setSize: vi.fn(),
+      setWindowButtonPosition: vi.fn(),
+      maximize: vi.fn(),
+      show: vi.fn(),
+      loadFile: vi.fn(),
+      loadURL: vi.fn()
+    }
+    browserWindowMock.mockImplementation(function () {
+      return browserWindowInstance
+    })
+
+    createMainWindow(null)
+
+    const syncListener = vi
+      .mocked(ipcMain.on)
+      .mock.calls.find(([channel]) => channel === 'ui:sync-traffic-lights')?.[1]
+
+    expect(syncListener).toBeTypeOf('function')
+
+    syncListener?.({} as never, 1.2)
+
+    if (process.platform === 'darwin') {
+      expect(browserWindowInstance.setWindowButtonPosition).toHaveBeenCalledWith({ x: 16, y: 18 })
+      return
+    }
+
+    expect(browserWindowInstance.setWindowButtonPosition).not.toHaveBeenCalled()
+  })
 })
diff --git a/src/main/window/createMainWindow.ts b/src/main/window/createMainWindow.ts
index 6d7c604f13c..2c9de1c647c 100644
--- a/src/main/window/createMainWindow.ts
+++ b/src/main/window/createMainWindow.ts
@@ -38,7 +38,7 @@ const TRAFFIC_LIGHT_RADIUS = 6
 const TRAFFIC_LIGHT_X = 16
 
 function syncTrafficLightPosition(win: BrowserWindow, zoomFactor: number): void {
-  if (win.isDestroyed()) {
+  if (process.platform !== 'darwin' || win.isDestroyed()) {
     return
   }
   const y = Math.round(TITLEBAR_CSS_CENTER * zoomFactor - TRAFFIC_LIGHT_RADIUS)
diff --git a/src/renderer/src/lib/ui-zoom.ts b/src/renderer/src/lib/ui-zoom.ts
index 12d3aa0ccb5..7ab1a00e19f 100644
--- a/src/renderer/src/lib/ui-zoom.ts
+++ b/src/renderer/src/lib/ui-zoom.ts
@@ -1,3 +1,5 @@
+const isMac = navigator.userAgent.includes('Mac')
+
 /**
  * Apply a UI zoom level change: sets webFrame zoom via the preload API,
  * updates the CSS variable used to compensate the traffic-light pad,
@@ -7,7 +9,9 @@ export function applyUIZoom(level: number): void {
   const zoomFactor = Math.pow(1.2, level)
   window.api.ui.setZoomLevel(level)
   document.documentElement.style.setProperty('--ui-zoom-factor', String(zoomFactor))
-  window.api.ui.syncTrafficLights(zoomFactor)
+  if (isMac) {
+    window.api.ui.syncTrafficLights(zoomFactor)
+  }
 }
 
 /**
@@ -18,5 +22,7 @@ export function syncZoomCSSVar(): void {
   const level = window.api.ui.getZoomLevel()
   const zoomFactor = Math.pow(1.2, level)
   document.documentElement.style.setProperty('--ui-zoom-factor', String(zoomFactor))
-  window.api.ui.syncTrafficLights(zoomFactor)
+  if (isMac) {
+    window.api.ui.syncTrafficLights(zoomFactor)
+  }
 }