title: F12 developer tools in IE9 not working for some sites
body: <p>I can launch the F12 developer tools in IE9, but for some sites, they don't do anything. The window opens but sits with the word "Loading..." in the HTML tab, and none of the controls work.</p>
  
  <p>Any idea what might be wrong?</p>
  
  <p><strong>UPDATE</strong> I checked the network tab with Chrome and do not see any hanging requests.  Further, the page itself is responsive in IE.</p>