You bring up a good point. What qualifies as a mask? Do fake beards and mustaches count? What about religious face coverings? What about people who have prosthetic noses? I have a feeling this is going to be a tricky one for them to enforce in any sort of reasonable way.

Brendan Eich is a big ole dickhead. He’s kind of like if Elon Musk was actually a competent engineer.

This website has a really extensive writeup on Firefox privacy and security hardening that I learned a couple of tricks from.

Besides that, you can search the Mozilla support forums as there are tons of threads there with questions and answers about Firefox privacy and security.