I opened my world from 1.15.2 in 1.16.1 and there some strange things:
- no loot from breaking minecart in survival by hand or by cactus
- commands works but there is no feedback from them. tried to use /gamerule - no effect. when i wrote any command in command block they works fine but there still no any output - in output line of command block only symbol "-"
Also i tried to optimize world and problem have not been solved
When i created new world in 1.16.1 everything was fine.