Steps to Reproduce:
Create a new world in Creative or Survival.
Place several paintings on solid walls
Save and exit the world.
Reopen the world.
Observe that some paintings may break/fall off on their own.
Note: Since the issue occurs randomly, not every time you load the world there will be broken paintings — but it may happen occasionally.
Hi!
Thank you for your report!
We're already tracking this issue at MCPE-181306, so I will resolve and link this ticket as a Duplicate.
I suggest also to browse through the main issue for potential fixes.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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