When you enter powder snow, you will slowly freeze. When you exit powder snow, it takes some time for you to unfreeze and while you are unfreezing, your movement speed is slowed until you unfreeze completely. When you exit the world and then re-join, your player will become stuck in the state between unfreezing and freezing and you will be permanently slowed down until you enter powder snow again.

Steps to Reproduce:

1. Enter powder snow
2. Stay in it until you're frozen
3. Exit powder snow (notice you walk slowly)
4. Exit the world
5. Re-join the world

Observed Results:

The player remains at the slowed down speed from freezing and cannot unfreeze completely until they enter powder snow again.

Expected Results:

The player unfreezes normally and is able to walk at normal speed again.

I have also created a video demonstrating this bug: https://youtu.be/avDtxPrt8nI