Potential OptiFine incompatibility on 1.12.2

[Adtsd24]

(TYPE: bug, RESULT: unavoidable crash)

So, yea.... basically, even if I only install MixinBooter (required for VanillaFix) and VanillaFix itself on 1.12.2 (along with OptiFine, but other than that, no more mods!), it bricks the entire game. It just crashes with an unknown error. With just OptiFine (i am not sure if its the same without OptiFine)! I tried renaming MixinBooter's JAR to be something like !mixin.jar to make it load first, then VanillaFix is _vanillafix.jar (or something like that), but nope.

This was an issue when I was making a 1.12.2 modpack. Had to remove VanillaFix from my modpack so that it frickin launches.

VanillaFix version: not sure, most probably 1.0.10-150 (latest for 1.12.2 on CurseForge)
OptiFine version: HD U G5
MixinBooter version: 10.2
Minecraft version: 1.12.2