title: window.close not working in firefox, after using window.open
body: <p>I'm trying to close the present window by clicking a button. I know window.close() could only work when the window is owned by javascript. </p>
  
  <hr>
  
  <p>So I use <code>window.open()</code> before, then close that window like:</p>
  
  <pre><code>self.name = "close";
  window.open("","close");
  self.opener = null;
  self.close();`
  </code></pre>
  
  <hr>
  
  <p>This works in Chrome and in older versions of Firefox, but not in FF14. 
  So how can I close a window in FF14?
  thanks!</p>
  
  <p>I run the following javascript in FF console.
  It works in IE and Chrome.</p>
  
  <pre><code>win=window.open('','_self');
  win.close();------undefined
  </code></pre>