title: How to access the webpage DOM rather than the extension page DOM?
body: <p>I'm writing a Chrome extension and trying to overlay a <code>&lt;div&gt;</code> over the current webpage as soon as a button is clicked in the popup.html file.</p>
  
  <p>When I access the <code>document.body.insertBefore</code> method from within popup.html it overlays the <code>&lt;div&gt;</code> on the popup, rather than the current webpage.   </p>
  
  <p>Do I have to use messaging between background.html and popup.html in order to access the web page's DOM? I would like to do everything in popup.html, and to use jQuery too, if possible.</p>