<?xml version="1.0"?>
<window xmlns:html="http://www.w3.org/1999/xhtml"
        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
        onload="loaded()">
<hbox flex="1">
  <html:style>
    /* Make sure our splitter's background doesn't depend on its hover styles */
    splitter {
      background-color: yellow;
      -moz-appearance: none;
    }
  </html:style>
  <script>
  function loaded() {
    document.documentElement.getBoundingClientRect();
    document.getElementById("s").setAttribute("state", "collapsed");
  }
  </script>
  <iframe width="200" src="data:text/html,hello"/>
  <splitter collapse="before" resizeafter="farthest" width="200" id="s">
  </splitter>
</hbox>
</window>