Minecraft Version

1.20.2

ModLoader

Fabric

Shimmer version

1.20.1-0.2.3

Modpack info or mod list(please reduce mod range)

https://www.curseforge.com/minecraft/modpacks/fabulously-optimized

The latest.log file and hs_err_pidXXX if exists

https://pastebin.com/PAqzSAyu & https://pastebin.com/C5WPg7AW

optifine , Rubidium , flywheel or any rendering related mods. mod version is required.

Not sure, but using Sodium, Lithium, Phosphor, etc fabric performance mods.

Issue description

Exit Code: -1. Game crashed on boot, unsure of incompatibilities. Crash log & Latest log posted above.

Steps to reproduce

1. Use Fabulously Optimized Modpack.
2. Add Shimmer mod to the mods folder
3. Boot Minecraft
4. Behold, the game crashes.

Other information

No response

Shimmer isn't compatible with Minecraft 1.20.2

Ah, had assumed it was given the compatibility range said 1.20-1.20.2 on Modrinth.
Thanks for the notice.