Minecraft 1.12.2
Forge 14.23.5.2860
MixinBooter 10.5

After adding MixinBooter 10.5 to a pack it immediately crashes on launch even before the game windows is displayed. Disabling MixinBooter allows the game to start and load normally.

latest.log

debug.log

Thank you all! Through the process of elimination I have determined this to be an issue (conflict?) with SuperMartijn642's Core Lib versions 1.1.12 and higher. Downgrading SuperMartijn642's Core Lib to 1.1.11 allows the game to load without removing MixinBooter.

Thanks Howard appreciate the extra information (I've been away from the modded Minecraft scene for a bit). I replaced Phosphor with Alfheim but unfortunately am still getting a crash:

latest.log

You are using Java 8...

Also fugue and scalar not exists.

They are not on cleanroom... So java 8 is correct.

oh mb then

VanillaFix is outdated and unsupported, please use updated forks instead like https://www.curseforge.com/minecraft/mc-mods/lolasm

Thanks for the info about VanillaFix! I replaced it with CensoredASM but unfortunately it's still crashing:

latest.log

Thanks for the info about VanillaFix! I replaced it with CensoredASM but unfortunately it's still crashing:

latest.log

Also, phosphor for 1.12.2 is outdated too, replace with https://www.curseforge.com/minecraft/mc-mods/alfheim-lighting-engine

Thanks Howard appreciate the extra information (I've been away from the modded Minecraft scene for a bit). I replaced Phosphor with Alfheim but unfortunately am still getting a crash:

latest.log

Try to remove Performant mod