### 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.cc
if (IsGuest()) {
    NativeWindow* owner_window = nullptr;
    if (embedder_) {
      
      auto* relay =
          NativeWindowRelay::FromWebContents(embedder_->ontents());
      if (relay)
        owner_window = relay->GetNativeWindow();
    }
    if (owner_window)
      SetOwnerWindow(owner_window);
  }
  ontents()->SetUserData(kElectronApiWebContentsKey,
                              std::make_unique<UserDataLink>(GetWeakPtr()));
}
#if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
void WebContents::InitWithExtensionView(v8::Isolate* isolate,
                                        content::WebContents* ontents,
                                        extensions::mojom::ViewType view_type) {
  
  type_ = GetTypeFromViewType(view_type);
  if (GetType() == Type::kRemote)
    return;
  
  Observe(ontents);
  InitWithWebContents(ontents, GetBrowserContext(), IsGuest());
  inspectable_ontents_->GetView()->SetDelegate(this);
}
#endif
void WebContents::InitWithWebContents(content::WebContents* ontents,