<?xml version="1.0"?>
<window xmlns:html="http://www.w3.org/1999/xhtml"
        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
  <box>
    <html:canvas width="300" height="300" style="background-color:lime; width: 300px; height: 300px"/>
  </box>
</window>
