<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<bindings xmlns="http://www.mozilla.org/xbl">
<binding id="foo">
<content>
<iframe xmlns="http://www.w3.org/1999/xhtml" src="javascript:void 0"><children xmlns="http://www.mozilla.org/xbl"/></iframe>
</content>
</binding>
</bindings>
</head>
<body>
<span style="-moz-binding: url(#foo)"></span>
</body>
</html>