title: Check readyState of a window opened using window.open
body: <p>I have a JS script that opens a pdf in a new tab. </p>
  
  <pre><code>var newWindow = window.open("url", "docWindow");
  </code></pre>
  
  <p>Is it possible to check if that document has loaded without running a script on that window, to check the <code>readyState</code> status of that document from the original tab?</p>