Minecraft 1.21.1
NeoForge 21.1.66
MFFS 5.4.6 and 5.4.12
Java 21.0.3 - aarch64

I'm trying to play on a Lenovo Slim 7x with the X Elite. I know this is a niche situation. It's playable, I'm just taking a big FPS hit.

I originally saw it in a mod pack, but I've narrowed it down to just MFFS. Issue will present itself from spawn in a new world. It happens when the graphics are set to fast, or fancy. It does not happen when set to fabulous. It's easily repeatable by just turning and moving. However, it isn't constant.

Modpack

Only MFFS