<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<bindings xmlns="http://www.mozilla.org/xbl"><binding id="foo"><content><frame xmlns="http://www.w3.org/1999/xhtml"><children xmlns="http://www.mozilla.org/xbl"/></frame></content></binding></bindings>
</head>
<frameset
onload="document.getElementById('y').appendChild(document.createElementNS('http://www.w3.org/1999/xhtml', 'span'));"
style="-moz-binding: url(#foo)"
>
<frame id="y"></frame>
</frameset>
</html>