Startup Issue with Minecraft - Server Not starting, even after creating a fresh server instance

System Information

Field Value
Operating System Linux - Ubuntu 26.04 on x86_64
Product AMP ‘Deimos’ v2.7.2.4 (Mainline)
Virtualization None
Application Minecraft
Module MinecraftModule
Running in Container No
Current State Failed

Problem Description

Issue

java.util.concurrent.ExecutionException: java.lang.IllegalStateException: No key dimensions in MapLike[{}]; No key seed in MapLike[{}]
	at java.base/java.util.concurrent.CompletableFuture.wrapInExecutionException(CompletableFuture.java:345) ~[?:?] {}

Reproduction Steps

  • Create new instance
  • Switch server version from Official Default to Neoforge 1.21.228
  • Server does not start after seemingly doing nothing other than switching the version