Reinstalling is waste of time, just let you know because the settings are kept, so nothing changes, issues remain.
Just create new profile.
Forks are pretty valuable to Firefox development, and it's helpful for Firefox marketshare too because they use the same UA as Firefox, so website must support Firefox.
Even Firefox devs said they observe Firefox forks to see their idea and bring back to Firefox, just compare recent new features of Firefox to Zen/Floorp, you would see that the idea of:
And many small things.
Yep, waiting for this feature so userChrome.js cook-ers can turn it into Tree Style Tab Group like Sidebery, with this config exposed it would be surprised if it takes long for us users to try the test version.
Smart Tab Group is pretty hype too.
This useless feature for what ? They implemented this because Google forcing them to do so I guess.