title: 'window.open' blocked by Firefox
body: <p>I use <code>window.open</code> and call it at the document <code>ready</code> event, but it is blocked by a popup blocker in Firefox. Then I added this to the function and make a call of this function from a button and then trigger the button click without success: </p>
  
  <pre><code>$(function(){    
      abcd();    
  });
  
  
  function abcd(){
      var popup = window.open("http://localhost/johndyer-mediaelement-7ed6c51/demo/index.php","mypopup","width=500,height=300");       
   }
  </code></pre>
  
  <p>Is there some way to open an external popup window or new tab on browser when the page loaded?</p>