So, turns out my previous comment, which I have now deleted, was due to a false positive while troubleshooting Firefox to find what caused an ungodly high memory usage (>95% of RAM eaten). There are still some problems with Dark Reader, it won't remember the settings for some websites or won't turn itself on or off on some pages for some unknown reasons, but, overall, it does it's job in a good way.

Excellente extension !

Great add-on, very useful for using my computer at night. The only thing is that I can't seem to turn it off? I can adjust the settings and switch between Dark/Light modes, but when I try to use the "Off" button or the keyboard shortcut nothing happens. Several times, when I've been using my computer in the day and didn't want an extremely dark or desaturated screen on webpages, I've just uninstalled the extension and reinstalled it later. This is obviously very annoying, though.

EN:
The best extension of its kind. Everything stated is there. Safe, open source and mozzila tested, updated regularly.

RU:
Лучшее расширение в своем роде. Всё заявленое есть. Безопасно, открыт исходный код и проверен mozzila, регулярно обновляется.

A great extension for the eye

well it works, but does not work as i need it to. i want it to be off and only toggle on for specific pages, not HAVE to be on all time for all pages just to toggle it off again for all the pages... just for the sake of having a few pages in dark mode. and it slows down the browser a lot on my low-end notebook. the devs should should check out how this extension is really annoying on different artists bandcamp pages. i listen to a lot of music from there and have to toggle off for pretty much every single page. i also have to say that i tried out about 2 years ago and still the same issue. just not for me...