I've had two crashes so far, both on a server. The crashes both happened when a player right-clicked (inserted) into a barrel. The first crash was a hopping barrel into a normal barrel, rightclicking the hopping barrel. The second was a normal barrel alone.

crash report

Minecraft 1.12.2
Forge 2655
charset 0.5.0.244

If you need any other information just let me know.

Duplicate of #229

Side note, both crashes happened within 15 minutes of a server restart, after the crash the server restarted and everything was fine till the next scheduled restart.