When placed chains to hang lanterns from behind, the lantern remains hanged in the air when the chain is broken.

This works as intended. Lantern hanging from the chain.

This should not happen. Lantern breaks when the block it is hanging is destroyed.

Further testing reveals that this mod does allow to place lanterns anywhere, which should also not happen. I dont know if is an intended feature, but could be awesome if there is an option to disable this behaviour as it does not have nothing to do with the mod, that is about modifying the chains behaviour and not about hanged lanterns.