the best

THIS IS COOL it's like completely black and it is fast, and dark hence it's name :)

Real lifesaver after 94.0.1 f*ked up my userChrome settings!
To remove white frame over selected tab in FF 102 (add to userChrome.css):
.tab-background {
outline: none !important;
}

i like amoled black

Plain Black. Hence the title - Good.

very cool, actual black theme

True black and nice readibility, that's what i was searching for :)