The Bug:

Large-sized mobs such as sniffers and ravagers cannot move while in water.

Steps to Reproduce:

1. Locate a fairly large body of water and obtain a sniffer spawn egg.
2. Spawn the sniffer in the water and observe its behavior for a while.
3. Take note of how it never attempts to change its position while in the water; it can only adjust its rotation.

Observed Behavior:

If a large mob is spawned in water, they will be unable to move. They can adjust their rotation but cannot change their position. In some rare cases, the large mob can sometimes jitter rapidly while trying to move forward.

Expected Behavior:

Large-sized mobs such as sniffers and ravagers would be able to move when in water.