title: .NET NotifyIcon displays a toast notification twice in Windows 10
body: <p>I use the .NET Framework System.Windows.Forms.NotifyIcon class to display a tray icon and tray notifications. When I call ShowBalloonTip on its instance, first the previously displayed notification displays again, then it hides, and only after a while does the expected one is displayed. It seems that historical notifications are displayed first unless I remove them manually from the notification center.</p>
  
  <p>What can I do programmatically to prevent showing the historical notifications again?</p>
  
  <p>Here's how I initialize the notify icon:</p>
  
  <pre><code>notifyIcon.Icon = Properties.Resources.tray_icon;
  notifyIcon.Visible = true;
  
  notifyIcon.BalloonTipTitle = Language.TrayMessageTitle;
  </code></pre>
  
  <p>Here's how I show the toast:</p>
  
  <pre><code>notifyIcon.BalloonTipIcon = icon;
  notifyIcon.BalloonTipText = message;
  notifyIcon.ShowBalloonTip(0);
  </code></pre>
  
  <ul>
  <li>The icon is either ToolTipIcon.Error or ToolTipIcon.Info, and I don't show a toast with the same icon twice, so they always toggle. But this does not seem to matter.</li>
  <li>The timeout param is 0, because it's not used since Windows Vista.</li>
  <li>The toast is displayed as a result of an application state change, not as a result of a user action like clicking.</li>
  </ul>