Donkey turned invisible after I hopped off him. He still has sound but cannot be riden and has no visible hitbox.

Put the summary of the bug you're having here

What I expected to happen was...:
I would still see him and be able to ride him again

What actually happened was...:
He turned invisible, He still has sound but cannot be ridden and has no visible hitbox while using f3

Steps to Reproduce:
1. I am not sure how this happened.
2. ...
3. ...