This is to fix a bug in observer mode such as guild wars.

If you have a pet in the slot and it respawns every time you teleport, it will affect you.
If you have a mount in the slot and it respawns every time you teleport, it will affect you.
It only affects you if the mount is following you and you get off the horse while in the observer.
The latter also applies to the horse.
The error consists in having any of the points described above that will make the pet, mount or horse publicly visible while the player is in spectator mode.

Lets start ;