private async void InnerWebView_DOMContentLoadedAsync(WebView sender, WebViewDOMContentLoadedEventArgs args)
 {
     WebRing.IsActive = false;
     NativeLoginPanel.SetVisibility(true);
     try { await GetVerificationCodeAsync(); } catch { /* ignore */ }
     try {
         await AskWebViewToCallbackAsync();
     } catch (Exception e) {
         Debug.WriteLine("error:\n" + e.StackTrace);
     }
 }
 public LoginPage()
 {
     this.InitializeComponent();
     NativeLoginPanel.SetVisibility(false);
 }