Minecraft 1.16.4 crashes every time (before showing the loading screen) when OptiFabric is installed in the mods folder!

temp fix:

it works if you downgrade fabric API to [1.16.4] Fabric API 0.28.4

We need a crash log in order to know what is going on here.

This might be the new render events also conflicting with optifine. You may need to consult with optifabric to fix it.

This is my log using the 29.0 api and optifabric

22:56:37.498
launcher
main
Preparing to launch minecraft client for fabric-loader-0.10.8-1.16.4
22:56:38.536
launcher
main
Checking installations.
22:56:38.544
launcher
main
Minecraft client fabric-loader-0.10.8-1.16.4 is ready to start.
22:56:38.544
launcher
main
Starting!
22:56:38.618
launcher
main
Using default game log configuration client-1.12.xml (outputs XML)
22:56:39.215
FabricLoader
main
Loading for game Minecraft 1.16.4
22:56:39.556
Fabric|Loader
ForkJoinPool-1-worker-2
The mod "infinityfix" contains invalid entries in its mod json:

• Unsupported root entry "side" at line 22 column 11
  22:56:39.693
  Fabric|Loader
  ForkJoinPool-1-worker-11
  The mod "autoconfig1u" contains invalid entries in its mod json:
• Unsupported root entry "$schema" at line 2 column 14
  22:56:39.720
  Fabric|Loader
  ForkJoinPool-1-worker-1
  Non-Fabric mod JAR at "C:\Users\alber\AppData\Roaming.minecraft\mods\preview_OptiFine_1.16.4_HD_U_G6_pre5.jar", ignoring
  22:56:39.726
  Fabric|Loader
  ForkJoinPool-1-worker-8
  The mod "autoconfig1u" contains invalid entries in its mod json:
• Unsupported root entry "$schema" at line 2 column 14
  22:56:39.727
  Fabric|Loader
  ForkJoinPool-1-worker-4
  The mod "autoconfig1u" contains invalid entries in its mod json:
• Unsupported root entry "$schema" at line 2 column 14
  22:56:39.762
  Fabric|Loader
  ForkJoinPool-1-worker-8
  The mod "autoconfig1u" contains invalid entries in its mod json:
• Unsupported root entry "$schema" at line 2 column 14
  22:56:39.767
  Fabric|Loader
  ForkJoinPool-1-worker-13
  The mod "autoconfig1u" contains invalid entries in its mod json:
• Unsupported root entry "$schema" at line 2 column 14
  22:56:39.866
  Fabric|Loader
  main
  [FabricLoader] Loading 96 mods: [email protected]+cbe9176f3a, [email protected]+6a2618f53a, [email protected], [email protected]+build.28, [email protected]+1.16.4, [email protected], [email protected]+cbe9176f3a, [email protected], [email protected], [email protected]+a03e98793a, [email protected]+9a6c75813a, [email protected]+6a2618f53a, [email protected], [email protected]+cbe9176f3a, [email protected], [email protected]+ab87788d3a, [email protected], [email protected]+build.1, [email protected], [email protected], [email protected]+6a2618f53a, [email protected], [email protected], [email protected]+build.1, [email protected]+6a2618f53a, [email protected]+6a2618f53a, [email protected], [email protected]+build.1, [email protected]+6a2618f53a, [email protected]+ffb68a873a, [email protected]+build.17, [email protected]+build.1, [email protected]+6a2618f53a, [email protected]+6a2618f53a, [email protected]+1.16, [email protected]+cbe9176f3a, [email protected]+2a4333d33a, [email protected]+build.1, [email protected]+6a2618f53a, [email protected], [email protected], [email protected], [email protected]+a03e98793a, [email protected], [email protected], [email protected]+build.19, [email protected], [email protected], [email protected]+6a2618f53a, [email protected], [email protected]+6a2618f53a, [email protected], [email protected]+6a2618f53a, [email protected], [email protected]+build.2, [email protected], [email protected], [email protected], [email protected], [email protected]+6a2618f53a, [email protected]+b7f9825d3a, [email protected], [email protected]+6a2618f53a, [email protected], [email protected]+mc.1.16.4, [email protected]+79b23bee3a, [email protected]+6a2618f53a, [email protected], [email protected]+730711c63a, [email protected]+c26373133a, [email protected], [email protected]+build.1, [email protected]+552549d53a, [email protected], [email protected]+e77439c73a, [email protected]+e77439c73a, [email protected], [email protected]+2e23b97c3a, [email protected], [email protected]+cbe9176f3a, [email protected]+be155ae23a, [email protected], [email protected]+6a2618f53a, [email protected], [email protected]+4358fbc63a, [email protected]+build.51, [email protected]+6a2618f53a, [email protected], [email protected], [email protected], [email protected]+cbe9176f3a, [email protected]+cbe9176f3a, [email protected], [email protected], [email protected]+6a2618f53a, [email protected]+build.1
  22:56:39.868
  Fabric|Loader
  main
  Mod cleancut (mc1.16-2.1-fabric) does not respect SemVer - comparison support is limited.
  22:56:39.945
  mixin
  main
  SpongePowered MIXIN Subsystem Version=0.8.2 Source=file:/C:/Users/alber/AppData/Roaming/.minecraft/libraries/net/fabricmc/sponge-mixin/0.8.2+build.24/sponge-mixin-0.8.2+build.24.jar Service=Knot/Fabric Env=CLIENT
  22:56:41.060
  Smooth Boot
  main
  Smooth Boot config initialized
  22:56:41.950
  launcher
  main

Exception in thread "main" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:226)
at net.fabricmc.loader.launch.knot.Knot.init(Knot.java:141)
at net.fabricmc.loader.launch.knot.KnotClient.main(KnotClient.java:27)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:224)
... 2 more
Caused by: org.spongepowered.asm.mixin.transformer.throwables.MixinTransformerError: An unexpected critical error was encountered
at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:363)
at org.spongepowered.asm.mixin.transformer.MixinTransformer.transformClass(MixinTransformer.java:208)
at org.spongepowered.asm.mixin.transformer.MixinTransformer.transformClassBytes(MixinTransformer.java:178)
at org.spongepowered.asm.mixin.transformer.FabricMixinTransformerProxy.transformClassBytes(FabricMixinTransformerProxy.java:23)
at net.fabricmc.loader.launch.knot.KnotClassDelegate.getPostMixinClassByteArray(KnotClassDelegate.java:157)
at net.fabricmc.loader.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:150)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at net.optifine.reflect.Reflector.(Reflector.java:286)
at net.minecraft.class_128.method_559(class_128.java:101)
at net.minecraft.class_128.(class_128.java:54)
at net.minecraft.class_128.method_24305(class_128.java:425)
at net.minecraft.client.main.Main.main(Main.java:135)
... 7 more
Caused by: org.spongepowered.asm.mixin.injection.throwables.InjectionError: Critical injection failure: Callback method onRenderParticles(Lorg/spongepowered/asm/mixin/injection/callback/CallbackInfo;)V in fabric-rendering-v1.mixins.json:MixinWorldRenderer failed injection check, (0/1) succeeded. Scanned 1 target(s). Using refmap fabric-rendering-v1-refmap.json
at org.spongepowered.asm.mixin.injection.struct.InjectionInfo.postInject(InjectionInfo.java:408)
at org.spongepowered.asm.mixin.transformer.MixinTargetContext.applyInjections(MixinTargetContext.java:1291)
at org.spongepowered.asm.mixin.transformer.MixinApplicatorStandard.applyInjections(MixinApplicatorStandard.java:1042)
at org.spongepowered.asm.mixin.transformer.MixinApplicatorStandard.applyMixin(MixinApplicatorStandard.java:395)
at org.spongepowered.asm.mixin.transformer.MixinApplicatorStandard.apply(MixinApplicatorStandard.java:320)
at org.spongepowered.asm.mixin.transformer.TargetClassContext.applyMixins(TargetClassContext.java:345)
at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:569)
at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:351)
... 18 more
22:56:41.950
monitor
Process Monitor
Process crashed with exit code 1

same thing here, newest version of fabric api instantly crashes with Optifabric giving an exit code 0

Yeah, this is an optifabric issue to fix -- some of the places the new Fabric API targets are modified by optifine in an incompatible way. Chocohead/OptiFabric#130 and Chocohead/OptiFabric#128 are already open on the optifabric side.