U9 will release on December 21 2024
I am sorry for delay and also less content than 2.7 or 2.8
B16 will be release version
The gamerule 'SecondPress' is being removed in U9 due to the sound effects being removed.
The Z and R keys functionality have been removed
The gamerule will still be available in versions lower than U9.
Edit: The SecondPress gamerule will stay (not doing anything after U9)
