title: MutationObserver - how to detect dom changes within iframe
body: <p>Let me first explain the problem:
  My script has a mutationobserver, which detects added nodes, and does some processing on the content - like compare and highlight some values.
  The current implementation detects changes in the entire document body, the target looks like this</p>
  
  <pre><code>var target = document.querySelector('body');
  </code></pre>
  
  <p>Everything works well, except when there is an iframe.
  Some client pages have an iframe or multiple iframes, others do not.</p>
  
  <p>My script is added within a script tag in the parent document. </p>
  
  <p>Question:
  a) is it possible to get the same MutationObserver to detect changes in body and iframe ? ie everything in the dom including the iframe
  b) if it is not possible with a single observer, what is the alternate method? </p>
  
  <p>please note: my script can only go to the main/parent document</p>