Mobs Get Stuck In Their Pathing and constantly try and jump over slabs

Mobs will try and path to somewhere they can't go and will continue to try and get there. I've noticed in three separate spots in my world and two of them involve half slabs, one cobble, the other dark oak. The other spot is my horse pen which is made with dark oak fences. 

Here are gifs of the problem if these are allowed.

https://gfycat.com/rightcolddogwoodtwigborer

https://gfycat.com/piercingcompetentiberianchiffchaff