Dark mode
A very simple dark mode implementation based on a single css attribute "mix-blend-mode".
It is very small and easy to use: just click on extension to enable dark mode and click again to switch it off. Your choice is retained across all websites you activate the extension for.
It works well with almost any website or PDF document, but be aware that images may appear as negatives due to color inversion.
If you don't trust massive extensions implementing a simple feature, look no further!
This extension is free and open-source, and you are welcome to improve it!