<?xml version="1.0"?> <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"> <hbox style="display: block"> <button style="-moz-binding: none; width: 0; display: block; overflow: hidden; padding: 10px; border: 1px solid black; ">Correct</button> </hbox> </window>