After sleeping in a bed (light gray if that matters), then saving and quitting the realm has transformed the bed into an invisible half slab block. This block can be walked on, and the accompanying change in height is present. Again, the bed is gone. The wireframe outline that surrounds blocks gives the outline of the invisible slab, but here is where it gets very strange.

Interacting with the block with any item crashes the Realm. Placing any block in the same space crashes the Realm. The Realm will shut down for 5 minutes and then come back up. We have taken to avoiding the "cursed house" for now (which of course was MINE, the realm owner for extra laughs for my members) but what happened here? The only unusual thing about the last session was that I slept with a parrot on my shoulder? Not sure if that matters, just trying to be complete.