<?xml version="1.0"?> <!-- Intentionally testing XUL loaded through the XML content sink rather than the XUL content sink. --> <!DOCTYPE window> <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"> <hbox> <label value="test" flex="3" /> <label value="test2" /> <label value="test3" flex="1" /> </hbox> </window>