This bug happens in Treasure Wars, but I’m not sure if it works anywhere else, because I haven’t found a working spot to try this in another game or the hub.
It happens when you right click a double-slabbed block. The block will turn into a mossy stone block (custom Hive block), but this is only client side.
It only seems to only affect 1.20.30, and it should be able to be reproduced on any device.
It works on the map Ruins (Trios), and Sandstorm (Solos). Here’s 2 screenshots and a recording of this bug:
Ruins:
Sandstorm:
Recording: https://www.youtube.com/watch?v=2OAc5YUMVOs