Description

Version 1.2.1 broke item/block IDs in combination with other mods (AE2, Tech Reborn).

This is what I see in my world after upgrading from v1.2.0 to v1.2.1 (was a Fusion Reactor from Tech Reborn before):

Version info

Minecraft version: 1.18.2
Mod loader + version: Fabric 0.14.8

Hi, adding a few blocks is not supposed to cause such issues. In fact, many people updated successfully. This is probably a bad interaction caused by another mod, or it might also be a client/server syncing issue if you see the wrong blocks on your client, but the server still sees the right ones. Unfortunately, I am not able to help you further. :/