Here's the crash log:
https://pastebin.com/pkUyRksC

Okay thanks a lot !

It seems this time the cause of this crash is:

java.lang.AbstractMethodError: Receiver class com.github.crimsondawn45.fabricshieldlib.initializers.FabricShieldLib$$Lambda$4428/0x000001b481d40580 does not define or inherit an implementation of the resolved method 'abstract net.minecraft.class_3955 create(net.minecraft.class_2960, net.minecraft.class_7710)' of interface net.minecraft.class_1866$class_7711.

I will look into this when I get home.

Any news ?

Ok I've found the source:

    public static final SpecialRecipeSerializer<FabricShieldDecoratorRecipe> FABRIC_SHIELD_DECORATION_SERIALIZER;
    public static final RecipeType<FabricShieldDecoratorRecipe> FABRIC_SHIELD_DECORATION;

    static {
        //Registering Banner Recipe (Lib only)
        FABRIC_SHIELD_DECORATION = Registry.register(Registries.RECIPE_TYPE, new Identifier(MOD_ID, "fabric_shield_decoration"), new RecipeType<FabricShieldDecoratorRecipe>() {
            @Override
            public String toString() {return "test_recipe";}
        });
        FABRIC_SHIELD_DECORATION_SERIALIZER = Registry.register(Registries.RECIPE_SERIALIZER, new Identifier(MOD_ID, "fabric_shield_decoration"), new SpecialRecipeSerializer<>(FabricShieldDecoratorRecipe::new));
        }

I have been waiting for a week...can't play my game unless this gets fixed so please respond with anything :(

Sorry, its exam week for me, so I probably cant look into this until Thursday or Friday, but I'll see what I can do right now.

I looked up the classes and translated the error:

the lambda does not define or inherit an implementation of the resolved method 'abstract CraftingRecipe create(Identifier, CraftingRecipeCategory)' of interface SpecialRecipeSerializer$Factory.

Maybe this line changed?

FABRIC_SHIELD_DECORATION = Registry.register(Registries.RECIPE_TYPE, new Identifier(MOD_ID, "fabric_shield_decoration")

I'll check with an acutal IDE at home.

it's okay bro take your time, I just wanted a response nothing else.

Thanks for the work

Ok, so I found the issue. In 1.20.1, the specific name of the method is different than in 1.20.2. Since we usually just support the latest update, we went from 1.20, where it worked, to 1.20.2, where it also worked. We never checked 1.20.1 since we assumed we could catch anything different when we went to 1.20.2. So we are going to need to make a 1.20-1.20.1 release and a separate 1.20.2-1.20.4 release, as we did with 1.19.2. It's easy, so hopefully it'll be out by the end of today or tommorow.

Thank you so much ! I see how things can change between versions and understand it can be confusing 😅
Good work !

Yep, even little stuff between versions makes it break lol, like going from Registry to Registries forced us to make a new version. I just released the 1.20.1 version on Github, will be on curseforge/modrinth shortly.

Thanks a lot !!