Zombies, husks, drowneds, zombified piglins and giants contains z-fighting. in their heads and legs.

How to reproduce

1. Go to the spectator mode (this issue can also happen in other modes but its easier to reproduce in spectator mode)
2. Spawn zombie, husk, drowned, zombified piglin or giant
3. Go to their head or legs

         →  Notice how there is Z-fighting