Rimuru will take care of all your anilist custom css needs.
Whats the point in using this? Why not use automail?
Rimuru is lightweight and fast, Rimuru doesn't have any annoying features, Rimuru picks up the css from user bio and displays it on the screen. In a nutshell if you want to view your friends css but don't wanna sell your soul, use Rimuru. Otherwise you know where to go.
Download as
A packed extension file:
Download the extension file from releases and load it into your opera or firefox browser.
Source:
Download the whole repository and load it unpacked in your chrome or edge browser.