@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);

menuitem#tm-content-closetab,
menuitem#menu_FileQuitItem,
menuitem[oncommand="inspector.exit();"],
menuitem[oncommand="Local_Install.closeSidebar();"] {
    -moz-image-region: rect(16px, 96px, 32px, 80px) !important;
    list-style-image: url("chrome://cutemenus/content/res/mosaic.png") !important; 
}