Version Information

Java 17.0.6 from Debian 12 repository
Lithium Fabric 0.11.2 (affected both 1.20 and 1.20.1 versions)
Fabric loader 0.14.21
Fabric API 0.83
No other mods

Expected Behavior

Two worlds with single seed should be absolutely indentical, but they other

Reproduction Steps

• Load MC 1.20 / 1.20.1 with Fabric API and Lithium
• Create world with any seed (work in any biomes and seeds)
• Take screenshots to easier make compare easier
• Quit and recreate this world
• Done!

Random seed and cords (sorry, not saved):

Seed 1743770523999351415. XYZ: -909 77 -2623

Without Fabric API it work as Vanilla, how this location should look:

Vanilla work normally (generation indentical with lithium-only screenshot). Its realy FAPI bug

Does this also occur with only Fabric API, without Lithium?

Just tested by myself, the generation seems randomized with just Fabric API installed without Lithium.

This should probably be reported to the developers of Fabric API.

Vanilla bug: https://bugs.mojang.com/browse/MC-55596