### 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

12.0.1

### What operating system are you using?

Windows

### Operating System Version

Windows 10 Pro 2020

### What arch are you using?

x64

### Last Known Working Electron version

11.3.0

### Expected Behavior

The app works perfectly fine with an embedded video player.

### Actual Behavior

The app crashes when creating an element with an embedded video player.

### Testcase Gist URL

https://github.com/pavladan/mpv.js-on-react

Change the version of electron to 12.0.1 to see the crash, 11.3.0 works perfectly fine.

Note: In order to see the crash on 12.0.1, adjustments to the settings must be made
```
const win = new BrowserWindow({
    width: 1280,
    height: 574,
    autoHideMenuBar: true,
    useContentSize: process.platform !== "linux",
    title: "mpv.js example player",
    webPreferences: {
      nodeIntegration: true,
      plugins: true,
      enableRemoteModule: true,
      nodeIntegrationInSubFrames: true,
      contextIsolation: false,
      worldSafeExecuteJavaScript: false
    },
  });
```

shell/renderer/renderer_client_base.cc
gin_helper::Dictionary* process,
                                     content::RenderFrame* render_frame) {
  process->SetReadOnly("isMainFrame", render_frame->IsMainFrame());
  process->SetReadOnly("contextIsolated",
                       render_frame->GetBlinkPreferences().context_isolation);
}
void RendererClientBase::RenderThreadStarted() {
  auto* command_line = base::CommandLine::ForCurrentProcess();
#if BUILDFLAG(USE_EXTERNAL_POPUP_MENU)
  
  
  
  
  
  if (command_line->HasSwitch(options::kOffscreen)) {
    blink::WebView::SetUseExternalPopupMenus(false);
  }
#endif
#if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
  auto* thread = content::RenderThread::Get();
  extensions_client_.reset(CreateExtensionsClient());
  extensions::ExtensionsClient::Set(extensions_client_.get());
  extensions_renderer_client_.reset(new ElectronExtensionsRendererClient);
  extensions::ExtensionsRendererClient::Set(extensions_renderer_client_.get());
  thread->AddObserver(extensions_renderer_client_->GetDispatcher());
#endif
#if BUILDFLAG(ENABLE_PDF_VIEWER)