2026/06/17
That Firefox has a built-in way to persist user-written stylesheets per-site: https://toast.al/posts/visuallayout/2024-05-22_how-to-mess-up-system-fonts/#:~:text=Gecko%2Dbased%20browsers%2C%20like%20Firefox%20or%20Librewolf%2C%20have%20this%20built%2Din%20under%20about%3Aconfig%20toolkit%2ElegacyUserProfileCustomizations%2Estylesheets%20set%20to%20true%2C%20then%20editing%20%24PROFILE%2Fchrome%2FuserContent%2Ecss