I can confirm that downloaded a world with the bugged boxes and booting that up in single player, keeps the boxes as bugged. I still do not know of the initial case that caused the bug
I have only seen this on the Realm I have. I don’t know of a replication in single player. I can go ahead and download a copy of the realm world to single player to see if it persists.
Is there an easy way to upload a world file from my Xbox One? I also have the realm I access from my Xbox One which may make it easier