java.lang.NullPointerException: Cannot invoke "net.minecraft.class_1799.method_7960()" because the return value of "java.lang.ThreadLocal.get()" is null
at net.minecraft.class_2589.redirect$cff000$fabric-item-api-v1$hasStackRecipeRemainder(BrewingStandBlockEntityMixin_Fabric.java:1547)
at net.minecraft.class_2589.method_11029(BrewingStandBlockEntityMixin_Fabric.java:1039)
at net.minecraft.class_2589.method_31665(BrewingStandBlockEntityMixin_Fabric.java:128)
at net.minecraft.class_2818$class_5563.method_31703(LevelChunk_BoundTickingBlockEntityMixin.java:662)
at net.minecraft.class_2818$class_5564.method_31703(class_2818.java:716)
at net.minecraft.class_1937.method_18471(LevelMixin.java:482)
at net.minecraft.class_3218.method_18765(ServerLevelMixin.java:404)
at net.minecraft.server.MinecraftServer.method_3813(MinecraftServerMixin.java:948)
at net.minecraft.class_3176.method_3813(DedicatedServerMixin_Vanilla.java:283)
at net.minecraft.server.MinecraftServer.method_3748(MinecraftServerMixin.java:845)
at net.minecraft.server.MinecraftServer.method_29741(MinecraftServerMixin.java:2126)
at net.minecraft.server.MinecraftServer.method_29739(MinecraftServerMixin.java:270)
at java.base/java.lang.Thread.run(Thread.java:842)
Fabric API (https://github.com/FabricMC/fabric/blob/1.20.4/fabric-item-api-v1/src/main/java/net/fabricmc/fabric/mixin/item/BrewingStandBlockEntityMixin.java) modifies the last remainder mechanic, so there is no need to fix it on the Arclight side and it actually causes a mixin conflict: