OIDCClient LogoutAsync throwing SemaphoreFullException - wpf

Question

I'm connecting to Identity Server 4 from a WPF application and I am trying to perform a logout. However, I get a SemaphoreFullException in my WpfEmbeddedBrowser when calling _oidcClient.LogoutAsync(). Initally I thought maybe I shouldn't use the browser for logging out, but I don't think that is possible.
Here is the part calling the login and logout:
//prompt login
var options = new OidcClientOptions()
{
Authority = Current.Properties["IdentityServerAPIAddress"].ToString(),
ClientId = "wpf",
ClientSecret = "secret",
Scope = "openid offline_access WebAPI",
RedirectUri = "http://localhost/signin-oidc",
Flow = OidcClientOptions.AuthenticationFlow.AuthorizationCode,
Browser = new WpfEmbeddedBrowser()
};
_oidcClient = new OidcClient(options);
try
{
loginResult = await _oidcClient.LoginAsync();
logoutResult = await _oidcClient.LogoutAsync();
}
...
Here is the WpfEmbeddedBrowser:
private BrowserOptions _options = null;
public WpfEmbeddedBrowser()
{
}
public async Task<BrowserResult> InvokeAsync(BrowserOptions options, CancellationToken cancellationToken = default)
{
_options = options;
var window = new Window()
{
Width = 450,
Height = 750,
Title = "SiteMonitor Desktop Application Login"
};
var webBrowser = new WebBrowser();
var signal = new SemaphoreSlim(0, 1);
window.Show();
var result = new BrowserResult()
{
ResultType = BrowserResultType.UserCancel
};
webBrowser.Navigating += (s, e) =>
{
if (BrowserIsNavigatingToRedirectUri(e.Uri))
{
e.Cancel = true;
result = new BrowserResult()
{
ResultType = BrowserResultType.Success,
Response = e.Uri.AbsoluteUri
};
signal.Release();
window.Close();
}
};
window.Closing += (s, e) =>
{
signal.Release();
};
window.Content = webBrowser;
window.Show();
webBrowser.Source = new Uri(_options.StartUrl);
await signal.WaitAsync();
return result;
}
private bool BrowserIsNavigatingToRedirectUri(Uri uri)
{
return uri.AbsoluteUri.StartsWith(_options.EndUrl);
}

Answer 1

Set maxCout to 2 in SemaphoreSlim, it's wroks for me.
var signal = new SemaphoreSlim(0, 2);