feat: prevent initial window state drift (#2731)

Signed-off-by: Adam Setch <adam.setch@outlook.com>

Author: setchy

src/main/config.test.ts

@@ -35,5 +35,6 @@ describe('main/config.ts', () => {
     expect(WindowConfig.webPreferences).toBeDefined();
     expect(WindowConfig.webPreferences.contextIsolation).toBe(true);
     expect(WindowConfig.webPreferences.nodeIntegration).toBe(false);
+    expect(WindowConfig.webPreferences.backgroundThrottling).toBe(false);
   });
 });

src/main/config.ts

@@ -52,5 +52,9 @@ export const WindowConfig: BrowserWindowConstructorOptions = {
     nodeIntegration: false,
     // Disable web security in development to allow CORS requests
     webSecurity: !process.env.VITE_DEV_SERVER_URL,
+    // Keep the renderer painting when the window is hidden so Chromium never
+    // freezes the last frame. Without this, reopening the menubar window shows
+    // stale notification content until the next React re-render completes.
+    backgroundThrottling: false,
   },
 };