private void FlashMessage(string level, string message) { var id = Guid.NewGuid(); FlashMessages.AddOrUpdate(id, new Tuple <string, string>(level, message), (_, e) => new Tuple <string, string>(level, message)); Task.Delay(TimeSpan.FromMilliseconds(FlashDelay)).ContinueWith(_ => { FlashMessages.TryRemove(id, out var _); UpdateDisplay(); }); UpdateDisplay(); }