title: AddThis Facebook share button with popup
body: <p>I am trying to use AddThis for a Facebook and Twitter share button like this:</p>
  
  <pre><code>&lt;div class="addthis_toolbox addthis_default_style addthis_16x16_style"&gt;
  &lt;a class="addthis_button_facebook"&gt;&lt;/a&gt;
  &lt;a class="addthis_button_twitter"&gt;&lt;/a&gt;
  ...
  
  &lt;script type="text/javascript"&gt;
    var addthis_config = addthis_config||{};
    addthis_config.data_track_addressbar = false;
    addthis_config.data_track_clickback = false;
  &lt;/script&gt;
  &lt;script type="text/javascript" src="//s7.addthis.com/js/300/addthis_widget.js#pubid=ra-516a8c1a380e068d"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>(of course i also include the AddThis JavaScript.)</p>
  
  <p>The Twitter button opens a popup but the Facebook button opens in a new browser tab. Why does this happen? I need the Facebook share function to open in a popup too. A fullscreen tab just looks wrong and ugly.</p>