Of course you can. about:profiles root directory → open directory create a new file `chrome/userChrome.css` and put this into it: #main-window[tabsintit

Of course you can. about:profiles root directory → open directory create a new file `chrome/userChrome.css` and put this into it: #main-window[tabsintitlebar="true"]:not([extradragspace="true"]) #TabsToolbar > .toolbar-items { opacity: 0; pointer-events: none; } #main-window:not([tabsintitlebar="true"]) #TabsToolbar { visibility: collapse !important; } #sidebar-header { display: none; } toolbarbutton#alltabs-button { -moz-binding: 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} restart the browser It also removes some other junk like the new tab button.