title: window.open not opening window
body: <p>I'm trying to open a page in a popup as opposed to new tab - but whichever browser I try this simply opens in a new tab, not popup.</p>
  
  <pre><code>&lt;input type="button" value="new win" onclick="window.open('http://yahoo.com', 'width=500, height=400')"  /&gt;
  </code></pre>
  
  <p>Any reason why?</p>