<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<style type="text/css">

[class='anon'], #v { float: left; }
[class='anon']:first-line { word-spacing: 30ch; }
body { width: 30ch; }

</style>

<bindings xmlns="http://www.mozilla.org/xbl"><binding id="foo"><content><div class="anon"><span>A BCDE</span><children xmlns="http://www.mozilla.org/xbl"/></div></content></binding></bindings>

<script type="text/javascript">

function boom()
{
  document.body.insertBefore(document.createTextNode("fijkl"), document.body.firstChild);
}

</script>
</head>

<body onload="boom();" style="-moz-binding: url(#foo)"><div id="v">&#x202C;</div></body>

</html>