Sublime

Perfect ...

Works like a charm and easy to turn the lights back on. Thanks!

Funktioniert nicht 100% auf allen Seiten. Selektiv kann man für bestimmte Seiten den hellen Modus verwenden, der trotzdem etwas abdunkelt. Vielen Dank für diese tolle Erweiterung!

Easy to configure, not too complicated but with enough options (great to have darker and lighter dark modes!) and handy per site toggles.

Changes all websites to dark mode very reliably. There are occasionally smaller issues if pictures are in the background (text becomes hard to read).
Easily to revert to original. Very low performance penalty, which is worth to have all pages in dark mode.

It's a must to save your eyes! Some sites eventually break, however the extension can be easily deactivated specifically for those.