water only play sound while playing on server and everything else doesn't work:
video showing the problem:
https://youtu.be/uhTzVSqOcAs
Linked issues
Comments
i can confirm this swimming mechanics are broken no damage taken if oxygen runs out. This bug affects player interaction with water. The way to fix it is to log out then login multiple times. or set your game mode to creative then back to survival again. also side note server eats a lot of cpu power with only 1 player playing same with client. It is very noticeable.

Can confirm. Water is simply ignored for its "sinking" mechanic, and you can no longer swim inside it. This is only for servers.
The video is unavailable.