Horse Bug

Horses are able to be hit through fences.
What I expected to happen was...: The horse to stay in my *made area for them to test the breeding.*
Describe what you thought should happen here: I think they should've stayed in my area? But they just sort've glitched through.

*What actually happened was...:*The horse went through a fence when i hit it with a diamond sword
Describe what happened here: The The horse went through a fence when i hit it with a diamond sword

Steps to Reproduce:
1. what? I don't understand this? Sorry.
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