dynamic-height-1-ref.xhtml

<?xml version="1.0"?>
<?xml-stylesheet href="chrome://global/skin/"?>
<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
	xmlns:html="http://www.w3.org/1999/xhtml">
  <hbox align="stretch">
    <box style="height: 5em"/>
    <html:input value="YO"/>
  </hbox>
</window>