بواسطة ChoGGi (مطوّر) في يناير 1, 2012 · رابط دائم

if you meant that little + sign next to the tabs, that comes with firefox by default

copy this into userchrome.css, restart, and it should make the + always show

#tabbrowser-tabs>.tabs-newtab-button{display:-moz-box!important}