There are several cases.
Everything is fine until you open any of the chests.
when deleted after opening the chest by Y coordinates, a gradual increase in freezes, up to a crash from low performance. (I suppose it has something to do with the "IF" condition)

And so. This problem is both with additional modifications and on different versions of the forge. Optifine has nothing to do with it

p.s Loot Slash Conquer-1.12.2-0.6.2.2-alpha and other versions
crash-2022-09-07_23.18.10-client.txt