I have finally achieved my lifelong dream of getting Firefox down to only 1 bar along the top.

https://lemm.ee/post/3371892

I have finally achieved my lifelong dream of getting Firefox down to only 1 bar along the top. - lemm.ee

It’s so beautiful I might cry.

I believe it is Mac only, but have you seen Arc?
Arc from The Browser Company

Experience a calmer, more personal internet in this browser designed for you. Let go of the clicks, the clutter, the distractions.

That screenshot OP posted is clearly a windows computer.
They weren’t saying the screenshot was of Mac OS. They were saying they believe Arc is only for Mac OS.

Also, check out ArcFox, a way to implement some of Arc Browser’s design into Firefox.

Keep in mind that it is currently undergoing a rewrite.

GitHub - use-arcfox/arcfox: Make firefox flow like arc

Make firefox flow like arc. Contribute to use-arcfox/arcfox development by creating an account on GitHub.

GitHub
This is pretty cool! Just installed it. But the css doesn’t seem to load properly, following the tutorial. Do you also have weird stuff going on with the top bar still showing sometimes?
I’ll go to the grave with Firefox installed on my brain chip.