The bug
When a mob wearing leather boots is walking around on top of powdered snow, it will often end up spinning around itself for a period of time. In the same way as mobs do on waterlogged slaps and double layer carpets etc.
MC-205083
Mobs wearing leather boots spin around when walking on powder snow
Resolved
Fixed
6
Confirmed
Important
Mob behaviour
20w46a, 20w51a, 21w03a, 21w05a, 21w06a
21w13a
Retrieved
I can confirm that of all mobs i tested, only Skeletons and Stray were able to move around, other mobs only stood still.