<html xmlns="http://www.w3.org/1999/xhtml">
    <body>
        <table id="table">
        <caption id="c1">PASS: Text in caption 1</caption>
        </table>
        <script>
           document.body.offsetLeft;           
           var caption = document.createElement('caption');
           caption.appendChild(document.createTextNode('FAIL: Dynamically added caption'));

           var table = document.getElementById('table');
           var c1 = document.getElementById('c1');
           table.insertBefore(caption, c1);
           document.body.offsetTop;
           table.removeChild(caption);
        </script>
    </body>
</html>