See crash report attached.
This crash is triggered whenever the first chunk in the world loads, either by running a forceload command, or by joining the world.
The enabled data pack provides a custom biome and overwrites minecraft:overworld, and that has been fine for years. Disabling ticking/reload functions doesn't fix this.
World folder with data pack reduced to essentials only: https://www.mediafire.com/file/4e38p1miwd1pvmi/MC-277476_-_altered_world_copy.zip/file
Linked issues
duplicates 1
Attachments
Comments 4
Duplicate of MC-276585
Couldn't reproduce it in a new world, so here's a data-pack reduced version of my world.
https://www.mediafire.com/file/4e38p1miwd1pvmi/MC-277476_-_altered_world_copy.zip/file
EDIT: good catch! Indeed a duplicate. Didn't find that report due to it not actually mentioning the crash reason the game provides.
Does the data pack change the world height?