The brightness of Player arms and legs in the inventory abruptly changes when rotating

Every time the Player arms and legs in the inventory rotates (either by walking around/pushed by something, riding an entity, or simply holding an items), the brightness will abruptly changes and make the arms and legs very bright or very dark depending on which direction the arms or legs is rotated at.

Steps to reproduce:

• Method 1

1. Changes the UI Profile to Pocket, this just to make the reproduction easier since the player models does not follow cursor movement in Pocket and has a much bigger models, regardless this can be reproduce in Classic too

2. Open your inventory

3. Equips any items to your main hand and offhand

4. Observe

• Method 2

1. Same as steps 1 on Method 1

2. Creates a flowing water

3. Walk toward the flowing water and immediately open your inventory

4. Observe

Expected results:
The brightness of Player arms and legs smoothly changes, like in the previous version.

Observed results:
The brightness of Player arms and legs abruptly changes, it’s also darker/brighter than it should be.