/* Source file https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/tab_close_button_always_on_hover.css made available under Mozilla Public License v. 2.0 See the above repository for updates as well as full license text. */ /* Always show tab close button on hover and never otherwise */ .tabbrowser-tab .tab-close-button { display: none; } .tabbrowser-tab:not([pinned]):hover .tab-close-button { display: flex !important; align-items: center; }