Prefab causes a crash when a player builds a structure.
This only happened when prefab was installed on a dedicated server.
The crash does not happen when playing in a singleplayer world on the client.

The Fabric version used was 0.11.1
Fabric API 0.29.4 was installed.
Prefab 1.0.0 was isntalled.

latest.log

crash-2021-01-27_03.21.22-server.txt

Blast, I thought I got that one!
Will be an easy fix.

This has been fixed with version 1.0.1 which is now available on CurseForge and Modrinth.