Mozilla's self stated mission as a self proclaimed "global crew of activists" [1] is to "more than deplatform" [2] people they disagree with. Deplatforming just means censorship in this context and they want people they don't like more than censored, they want them off the internet completely. Pretty dangerous for a company making a browser to list infringing on people's human rights as a goal, but they've convinced themselves they're the good guys.
[1] https://blog.mozilla.org/en/mozilla/mozilla-brand-next-era-o...
[2] https://blog.mozilla.org/blogarchive/blog/2021/01/08/we-need...