Copper Golems can't open copper chests if the top is covered by a non-full block and the back or front are covered by any blocks

I have tried making an iron farm in the most recent snapshot. I had to place a non-solid block above the copper chest to be able to place a sign to stop the lava from destroying the farm. I also placed a hopper behind the copper chest. I can open the copper chest but my copper golem refuses to open it.

Steps to recreate:

summon a copper golem

place any non-full block above the copper chest

place any full or non-full block behind or infront of the copper golem

Expected result: Copper Golem opens copper chest and takes out the item

Actual result: Copper Golem wanders around aimlessly.