### 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.

### Problem Description

We need to load a custom error page when the certificate is invalid but without "isMainFrame" property we don't know when to load the custom error page using webContents.loadURL()

### Proposed Solution

webContents.on("certificate-error", ((event, url, error, certificate, callback, isMainFrame)

### Alternatives Considered

Not sure

### Additional Information

Not sure
shell/browser/api/electron_api_app.cc
Emit("new-window-for-tab");
}
void App::OnDidBecomeActive() {
  Emit("did-become-active");
}
#endif
bool App::CanCreateWindow(
    content::RenderFrameHost* opener,
    const GURL& opener_url,
    const GURL& opener_top_level_frame_url,
    const url::Origin& source_origin,
    content::mojom::WindowContainerType container_type,
    const GURL& target_url,
    const content::Referrer& referrer,
    const std::string& frame_name,
    WindowOpenDisposition disposition,
    const blink::mojom::WindowFeatures& features,
    const std::string& raw_features,
    const scoped_refptr<network::ResourceRequestBody>& body,
    bool user_gesture,
    bool opener_suppressed,
    bool* no_javascript_access) {
  v8::Isolate* isolate = JavascriptEnvironment::GetIsolate();
  v8::Locker locker(isolate);
  v8::HandleScope handle_scope(isolate);
  content::WebContents* web_contents =
      content::WebContents::FromRenderFrameHost(opener);
  if (web_contents) {