Not sure if this is intentional or not but when I spawn a fox with chickens inside powdered snow and they didn't get stuck
Steps to reproduce
1.-Make a pool of powdered snow
2.-Spawn a fox
3.-Spawn chickens or rabbits inside of powdered snow
4.-Observe, make sure the fox jumps in
Observed results
The fox didn't got stuck
Expected results
The fox should be stuck, just like in normal snow
This sounds intentional, due to the fact that foxes are light in minecraft, and they wouldn't just skip a mob, but i dunno.