I've made a simple script in python that essentially runs server on and off in order to pregenerate large amount of terrain (file attached). In rare occasions server happen to throw "Server-Worker-N died" upon generating chunk, and crash. I couldn't find any similar bug already reported.
EDIT:
I've made some more tests and it appears to be really bug in java 11 and maybe not in jar itself.
After switching to runtime bundled with launcher crashes stopped.
Will mark this as invalid for now, as only Java 8 is officially supported. If you recreate the problem using this version, we can re-open the ticket.