title: Can page rendering run simultaneously with JavaScript?
body: <p>I have an overridden GWT DialogBox that has as a widget overridden PagingScrollTable. 
  I have something like this in my code:</p>
  
  <pre><code>1) DialogBox dialog = new ...
  2) dialog.center(); 
  3) Window.alert("Hello"); 
  </code></pre>
  
  <p>In IE I would see alert after loading of table’s header but before loading of table’s content (about 1000 rows). But javascript is single-threaded language so how can it be? 
  May it be a browser issue or issue of my code?  </p>
  
  <p>Thanks!</p>