As far as using a fork of Firefox, if Firefox doesn’t live on, neither will these forks.
Why? The other teams have the source code, they can just continue extending it or just maintaining it.
And having just switched from Firefox to LibreWolf yesterday, it took all of 20 minutes to do. It's not like you'll be hung out to dry without the Internet if you are correct. You would just switch to another browser again.
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