Taming a horse will give you the "A complete catalouge" advancement.

Put the summary of the bug you're having here

What I expected to happen was...: To just tame the horse and move on.
What actually happened was...: I got the advancement for taming all cat variants "a complete catalouge". when i had only tamed 1 cat variant. This happened right after taming the horse.
 Describe what happened here: Tamed a horse, and it gave me the advancement for taming every cat variant in the game.

Steps to Reproduce:
1. Find a horse (Dont know if this is required, but tame a calico cat and only a calico cat first)
2. Ride on it until it is tamed.
3. You now have the "A complete catalouge" advancement.