title: Display a warning when leaving the site, not just the page
body: <p>This sounded like something almost impossible to do when it was presented to me. I know you can display a dialog box to confirm when leaving a web page. But is it possible to display a dialog box when leaving a site? </p>
  
  <p>I haven't been able to find/create anything that can read the address bar and know that you're leaving the site.</p>