crash-2024-10-12_22.53.22-fml.txt
java.util.ConcurrentModificationException
The game sometimes randomly crashes with this error message. Sometimes it boots up just fine (no crash).

MC Java 1.21.1
Neoforge 21.1.68
Sophisticated Core 1.21-0.6.44.719 (though happens in recent versions as well).

I fixed this a few days after the report, but forgot to close. So just use the latest release and you're good