Hide native tab bar in Firefox¶

In order to hide the tab bar in Firefox, one needs an alternative way to navigate the tabs. The Tree style tab is one such extension which can be installed for this. After installing Firefox, the following steps can be followed to do that,

1. Go to about:support in the Firefox address bar
2. Look for your profiles directory and open it:
3. Create a file named chrome/userChrome.css in your profile directory: Use the following command in Terminal

   mkdir chrome && touch chrome/userChrome.css
   

4. Populate the following CSS code:

   #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-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"] #sidebar-header {
     display: none;
   }
   .tab {
     margin-left: 1px;
     margin-right: 1px;
    }
   

5. Go to about:config in the Firefox address bar. Accept and continue when prompted with risk information

6. Search for toolkit.legacyUserProfileCustomizations.stylesheets and toggle it to true.

7. Close and restart Firefox browser.