title: Keep a pointer to a callback even when navigating to a new page in a popup window
body: <p>I'm working on a project which insists on using real modal windows. The current implementation works, it simply calls "showModalDialog" and uses the result that the dialog stores in "returnVal".</p>
  
  <p>However, on Chrome, when you navigate to a different page, this functionality no longer works. It's a documented bug.</p>
  
  <p>I'm changing it to use window.open. I can pass in a callback no problem... However, the popup window needs to be navigatable (it's to add an item to a DB, then return the items ID to the calling page). I can pass the callback in to the popup window, but when it navigates, I lose that callback...</p>
  
  <p>Is there any way I can keep a pointer to a callback even when navigating to a new page in a popup window?</p>