Firefox Proton Square

If you are like me and hate rounded tabs, this is for you.

Overall I understand why Mozilla went the direction they did with Proton to “modernize” the UI, but not to say that I have to like it.

These tweaks attempt to recreate the feel of Quantum with its squared tabs and menus, but in the Proton UI.

• Tab Design
  • General:
    • Connect with toolbar(Buttons like tabs)
    • Square corners
    • No spacer on left tab bar when windowed
  • Selected:
    • Add colored tab context line above selected tab
  • Unselected:
    • Divide Line: full height and colored like Quantum
    • Remove white space between tabs
• Menu Design
  • General:
    • Square corners on most popup menus

Suggested Tweaks (about:config)

• set browser.tabs.tabMinWidth to 150 px or desired width
• set widget.non-native-theme.gtk.scrollbar.round-thumb to false to square the scrollbar (linux only)
• change layout.css.devPixelsPerPx to scale the whole browser (1.0 represents 100% scaling)

How to Install?

1. Enable userChrome.css Support.
   • Go to about:config
   • toolkit.legacyUserProfileCustomizations.stylesheets to true
   • svg.context-properties.content.enabled to true
2. Find Profile Directory.
   • Go to about:support
   • Open Profile Directory
3. Copy File
   • create chrome directory at profile
   • copy files
4. Restart