I say "crash" because it doesn't seem as severe as other crashes (which boot me back to the main menu, thanks to VanillaFix), this one doesn't seem to do anything other than causing the ability to fail to cast. Seems to happen randomly, usually when I'm the only entity around.

https://paste.dimdev.org/rotopazabi.mccrash

Link doesn't work for me. Perhaps use a reliable site and not shitty dimdev crap.

Updated link: https://pastebin.com/mg7Nakh5

Dimdev is just hastebin, but it keeps it forever instead of clearing it after 30 days, plus custom MC syntax highlighting. VanillaFix mod autocreates the crash reports.