As I was playing survival on a flat world, I noticed a bat (it spawned during the night) flying around in the sitting position without its flying animation.

I checked with my friend who was on the server, and the bat animation was not working for him either.

Possibly multiplayer-only.

Unfortunately, I don't have a screenshot of it (and, frankly, I'm too lazy to relaunch Minecraft to get one).

Recreate this bug by creating a flat world and spawning a bat. (It might only happen with naturally-spawning bats, though.)

Basically, MCCE-5302 is happening on Java Edition.