i've been using night eye on firefox and it's honestly great. unlike some other extensions that just invert colors and make images look weird, this one actually converts the page so it looks natural. it's way easier on my eyes, especially at night.

i like that you can adjust the brightness and contrast if a specific site looks a bit off, but usually, it just works right away. the support team is pretty responsive too if you find a bug. definitely recommend it if you hate staring at bright white screens.