How to reproduce:
1. Teleport all chest minecarts in the world using
/tp @e[type=MinecartChest] @p
2. Destroy all minecarts with /gamemode 0
3. Look for enchanted books
MC-84240
Enchanted books in Minecarts (mineshafts) are corrupted
Resolved
Duplicate
0
That's a very clever way of testing the issue, but it's already been reported: MC-83897