<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
<head>
<style id="ss" type="text/css">
span, popupgroup { display: table; position: absolute; }
</style>
<script type="text/javascript">
function boom()
{
var ss = document.getElementById("ss");
ss.removeChild(ss.firstChild);
}
</script>
</head>
<body onload="boom();">
<span><xul:popupgroup/></span>
</body>
</html>