title: How to add items to / modify the forms default contextmenu
body: <p>Solution found here: <a href="https://stackoverflow.com/questions/4615940/how-can-i-customize-the-system-menu-of-a-windows-form">How can I customize the system menu of a Windows Form?</a>. Anyway, thanks for your help :)
  <br><br><br><br><br><br><br><br>
  I want to add a new item to the default contextmenu of a form, which appears when right clicked on the top bar (where the minimize box and maximize box are).</p>
  
  <p>I'd also prefer to to it programatically (not in the designer)</p>
  
  <p>I've tried this
  </p>
  
  <pre><code>public Form1()
  {
      InitializeComponent();
      this.ContextMenu.Add(new MenuItem("Test")); //-&gt;NullReferenceException
      this.ContextMenu = new ContextMenu(/*..*/); //-&gt; Not what I want
  }
  </code></pre>
  
  <p>
  which leads to a NullReferenceException.
  if I set <code>this.ContextMenu</code> it affects only the contextmenu that appears when you right click <b>into</b> the form, which I don't need in this case.</p>
  
  <p>I hope someone can help me out ^^ I know it needs to be possible somehow since I've seen it in a lot of Programs already</p>