title: Are your familiar with this code injected by firefox?
body: <pre><code>&lt;div id="atffc"&gt;
      &lt;object height="1px" width="1px" id="atff" data="//bin.clearspring.com/at/v/1/button1.6.swf" type="application/x-shockwave-flash"&gt;
          &lt;param name="wmode" value="transparent"/&gt;&lt;param name="allowScriptAccess" value="always"/&gt;
      &lt;/object&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>It only happens the first time you visit.</p>
  
  <p>And I checked there is no such code in source code.</p>