I'm glad this exists, and very impressed with how front-and-center their source code is, but I decided a while ago that I'm not installing random add-ons unless I have a very high level of trust in their integrity.

This looks mostly like CSS hack (even the little bit of JS there seems to mainly query the DOM and apply styles). Such things should IMO be packaged as userstyle files. I think people need to be reminded of the concept of userstyles, and how useful they are to remove the garbage web designers produce.

Stylus is a godsend: https://github.com/openstyles/stylus. Sad thing is, this used to be a built-in browser feature.

As a counterpoint, I find userstyles far less convenient than extensions. In my experience, they are more difficult to install, they work less often and break more easily (because of the "put this thing I hacked together on the internet and forget about it" mindset), don't auto update, are more difficult to find or discover, and the UI for managing/customizing them is horrible.

Sure, there's advantages too, and I like the idea of user styles/scripts, but after wasting some time on trying (and failing) to use them to customize my browsing experience on a few sites, I settled on a Dark Reader + Auto Reader Mode + uBlock combo that makes all of the internet nice and readable with almost no extra hassle.

It requires "all websites", so I pulled the code, read through it, packed it up and installed it manually in firefox ;)

Love this addon. It gives me the freedom to browse Medium again.