typeError: Failed to execute 'contains' on 'Node': parameter 1 is not of type 'Node Polymer
<p>I am trying to implement context menu using polymer paper menu. Whenever I remove node from dom. <code>polymer</code> is throwing error like this  </p>

<blockquote>
  <p>typeError: Failed to execute 'contains' on 'Node': parameter 1 is not of type 'Node'</p>
</blockquote>

<p>and I get the following error message:</p>

<p><a href="https://i.stack.imgur.com/KioEL.png" rel="noreferrer"><img src="https://i.stack.imgur.com/KioEL.png" alt="Error screenshot attached"></a></p>

<p>What shall I do?</p>