@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);
#bookmarks-ptf toolbarbutton:not([container="true"]) label,
#bookmarksBarContent toolbarbutton:not([container="true"]) label
{ display: none !important; }
#bookmarks-ptf toolbarbutton:not([container="true"]):hover label,
#bookmarksBarContent toolbarbutton:not([container="true"]):hover label
{ display: block !important; }