Sleeping players have very small hitboxes

The Bug:

Sleeping players have very small hitboxes.

Steps to Reproduce:

1. Get two players and label them "Player A" and "Player B".
2. Have "Player A" enable entity hitboxes by pressing "F3 + B".
3. Get "Player B" to place down a bed and begin sleeping in it.
4. Get "Player A" to look closely at the hitbox of the sleeping player.
5. Take note as to whether or not sleeping players have very small hitboxes.

Observed Behavior:

The hitbox of sleeping players is very small and is positioned around their heads.

Expected Behavior:

The hitbox would be made larger to cover the whole player model.