For the brave…
in the Advanced / Show debug settings menu, try:
Good luck, and please don’t swear at me if your viewer dies! By the way, the two images above were actually both taken with shadows enabled. The ‘with shadows’ image was taken with ‘High-res Snapshot’ enabled in the Advanced menu, while the shadowless image is a regular snapshot.
PS: I did try to check the covenant to see whether snapshots were specifically prohibited, but the covenant was so long that I almost lost the will to live.