Facebook container
Isolates Facebook to a container to prevent it from snooping on your internet activity.
Temporary Containers
Open tabs, websites, and links in automatically managed disposable containers.
Multi-Account Containers
Configure websites to always open in a specified container so that you don't have to log in every time.
ublock origin
privacy badger https://privacybadger.org/
https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab/
Chrome has a variable you can set to force dark mode using color inversion. This is useful for websites that don't have a dark mode setting.
chrome://flags/#enable-force-dark