Mob and Fence Interaction

Iron Golems walk normally at first, then seem to selectively aim for fences. Upon nearing the fence they jump on top and proceed to spin/not move until either the fence is broken or they are pushed off. Troubleshooting seems to find them able to move along fences, but not off of them.

To reproduce: build a fence on uneven terrain, where it is able to be jumped on from 1 side. The iron golem will proceed to climb on the fence and refuse to come down, even after pleading.