It was working beautifully until about 2 months ago when website loading slowed down a lot. When I disable the addon the sites load up instantly. The addon works perfectly fine on Chrome but for whatever reason it's not smooth on Firefox which is a shame since I prefer that browser. Hopefully it gets fixed soon.

the only thing which annoys me is that the scrollbar also is changed and hard to recognize - please don't touch the UI itself

Os navegadores deveriam vir com uma opção padrão para o tema dark ou noturno para web sites (isso é muito util para quem tem problemas de visão). Alguns concorrentes já tem essa opção

Great add-on.
The only reason for 4 stars is:

it doesn't work properly on outlook websites e.g. https://outlook.live.com/people

please fix it Alexander
thank you!

Очень нравился DR до момента, пока начал замедлять открытие страниц (а возможно и вообще их функционал) - об этом всплывает оповещение в браузере.

It is nice across most sites, but it disables channel art on YouTube. It was only after disabling this plugin I could see channel art in YouTube.

This is my favorite dark mode add-on for Firefox (and Chrome) right now, but it still has some things to be desired, such as a time-based dark-mode, and the fact that it can't control the "theme" so the search bar is dark too, and things like that. Consequently this add-on pairs best with the stock Dark theme for Firefox, which is a bit bland to me. Also, this add-on (and the Dark theme) cannot affect the appearance of any sites core to Firefox like the Add-ons page (which makes sense from a privacy and security standpoint, but not from a user experience standpoint). I'd also like to have more control over the colors and adjustments than just sliders or CSS code or Toggle buttons. It would also be nice if it could darken the screen before a site loads because the flash of bright white after clicking a link is quite jolting and unpleasant.
Dark Mode for Chrome (and maybe Firefox?) has a lot more flexibility in that realm, but it's just not as quick or intelligent as Dark Reader.
Also some of my complaints are more at the way Firefox handles add-ons, so there's not a lot that the developers can do about those things.