### Preflight Checklist

- [X] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/master/CONTRIBUTING.md) for this project.
- [X] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md) that this project adheres to.
- [X] I have searched the [issue tracker](https://www.github.com/electron/electron/issues) for a feature request that matches the one I want to file, without success.

### Electron Version

12.0.5

### What operating system are you using?

macOS

### Operating System Version

11.2.3

### What arch are you using?

arm64 (including Apple Silicon)

### Last Known Working Electron version

_No response_

### Expected Behavior

`document.hasFocus()` is only `true` for the window that has focus.

### Actual Behavior

Ever window reports `document.hasFocus()` to be `true` right after opening.

### Testcase Gist URL

https://gist.github.com/16e6fc829febd0cab115dfd0850a31be

### Additional Information

_No response_
shell/browser/api/electron_api_web_contents.h
bool HandleKeyboardEvent(
      content::WebContents* source,
      const content::NativeWebKeyboardEvent& event) override;
  bool PlatformHandleKeyboardEvent(
      content::WebContents* source,
      const content::NativeWebKeyboardEvent& event);
  content::KeyboardEventProcessingResult PreHandleKeyboardEvent(
      content::WebContents* source,
      const content::NativeWebKeyboardEvent& event) override;
  void ContentsZoomChange(bool zoom_in) override;
  void EnterFullscreenModeForTab(
      content::RenderFrameHost* requesting_frame,
      const blink::mojom::FullscreenOptions& options) override;
  void ExitFullscreenModeForTab(content::WebContents* source) override;
  void RendererUnresponsive(
      content::WebContents* source,
      content::RenderWidgetHost* render_widget_host,
      base::RepeatingClosure hang_monitor_restarter) override;
  void RendererResponsive(
      content::WebContents* source,
      content::RenderWidgetHost* render_widget_host) override;
  bool HandleContextMenu(content::RenderFrameHost* render_frame_host,
                         const content::ContextMenuParams& params) override;
  bool OnGoToEntryOffset(int offset) override;
  void FindReply(content::WebContents* web_contents,
                 int request_id,
                 int number_of_matches,
                 const gfx::Rect& selection_rect,
                 int active_match_ordinal,
                 bool final_update) override;