Horses get stuck on glass blocks.

I noticed that a horse falling down through a long tube of glass seem to get stuck somewhere on the way down.

This is puzzling since there seems to be nothing to stand on.

To reproduce: Create a glass wall. Spawn a horse on top and push it over the edge.

Expected result: The horse falls all the way down the side of the  glass wall.

Observed result: Sometimea, the horse stops in mid-air somewhere.