The Bug:

The player model in the inventory jitters and is choppy when changing states.

Outside of the inventory, when a player changes their state/pose, for example, entering the crawling animation, the animation is perfectly smooth and does not harshly jitter. However, inside the inventory, the player model is not smooth when changing states/poses and slightly jitters. Instead, it looks choppy and not smooth.

See the provided video for a narrated explanation. MC-265935.mp4

Steps to Reproduce:

1. Place down a trapdoor and stand in a way that will make you enter the crawling state when opening the trapdoor.
2. As soon as you interact in the trapdoor and you're in the process of changing your state, open your inventory and watch your player model closely.
3. Take note as to whether or not the player model in the inventory jitters and is choppy when changing states.

Observed Behavior:

The inventory player model jitters and is choppy.

Expected Behavior:

The inventory player model would be smooth and not jitter.