title: jQuery position() top is different in Chrome and Firefox
body: <p>When I run the following fiddle in Chrome and Opera, the position().top is returned as 0, but Firefox is returning 1 and IE return 0.5.</p>
  
  <p>How can I fix this?</p>
  
  <p><a href="http://jsfiddle.net/scottieslg/Loefza24/2/" rel="nofollow">http://jsfiddle.net/scottieslg/Loefza24/2/</a></p>
  
  <p>Html:</p>
  
  <pre><code>&lt;table id='testTable'&gt;
      &lt;thead&gt;
          &lt;tr&gt;&lt;td&gt;Test&lt;/td&gt;&lt;/tr&gt;
      &lt;/thead&gt;
  
      &lt;tbody&gt;
          &lt;tr&gt;&lt;td&gt;Body&lt;/td&gt;&lt;/tr&gt;
      &lt;/tbody&gt;
  &lt;/table&gt;
  
  &lt;div id='topPos'&gt;&lt;/div&gt;
  </code></pre>
  
  <p>css:</p>
  
  <pre><code>* { margin: 0; padding: 0 }
  #testTable {
      table-layout: fixed;
      width: 100%;
      padding: 0;
      margin: 0;
      border-collapse: collapse;
  }
  
  #testTable thead tr td {
      border: 1px solid #ccc;
  }
  </code></pre>
  
  <p>script:</p>
  
  <pre><code>$(document).ready(function() {
      var topPos = $("#testTable thead tr:nth-child(1)").position().top;
      console.log(topPos);
      $("#topPos").html("Top: " + topPos);
  });
  </code></pre>