Draco18s

You should fix that.

Your json is invalid. https://jsonlint.com/

1.12 is no longer supported. Update to at least 1.14 to recieve support.

https://github.com/MinecraftForge/MinecraftForge/issues/6287

minecraft:crafting_shapeless doesn't know what the fuck a "Potion" is, so that parameter is being ignored. Have you tried looking at the tipped arrow recipe that vanilla uses?

That is not data/minecraft/recipes, is it?

Check all the adjacent positions?

This. Because its less work.

This:

I'm not sure what you need docs for to copy-paste a function.

...You have to run a ray trace. Take the existing client side code, copy it, and put it where you need it (common code).

You will need your own IRecipe impelementation, as the existing ones do not care about nbt data. You can check Choonster's test mod for reference. https://github.com/Choonster-Minecraft-Mods/TestMod3/blob/1.12.2/src/main/java/choonster/testmod3/crafting/ingredient/IngredientNBTTestMod3.java

Its more than one block, but it does work. https://github.com/Draco18s/ReasonableRealism/tree/1.14.4/src/main/java/com/draco18s/harderores/world

Show what you tried.

Overwrite the vanilla json with your own. Its a datapack item, just like recipes.

Your capability registered object and the capability data are not the same thing. For example, this: https://github.com/Draco18s/ReasonableRealism/blob/1.12.1/src/main/java/com/draco18s/farming/entities/capabilities/MilkStorage.java#L28-L33 Returns a new instance of the class that holds the capability data. My capability attach event: https://github.com/Draco18s/ReasonableRealism/blob/1.12.1/src/main/java/com/draco18s/farming/FarmingEventHandler.java#L761 (Note: that is 1.12 code and there have been changes, but it should at least work as a template to understand what's going on)

You have told it to call a method called "getDefaultInstance" but this method does not exist anywhere I can find.

Yep, that's the relevant section.

Link to their site, for reference: http://minetaleapi.com/ Just based on what I'm seeing there, I think its more donation based then strictly "buy things for real money" but its hard to tell.

Create an empty json file with the same name as the recipe in the vanilla data folders and add it to your own assets in the same location (so, src/assets/data/minecraft/recipes)

The elytra flying code isn't handled by the elytra at all, but rather the player entity code (which checks for specifically the elytra item).

I wonder if Minecraft's source code (available in the external resources) has any crops that have code you could look at and utilize.

I would look at how vanilla does render capes, and learn from it, and write your own renderer for it. The elytra would also be a place to look (and IMO a batman cape is closer to elytra than a cosmetic).

Don't make capes. Mojang declared exclusivity over capes. Make literally any other cosmetic you want.

I could not remember if this was actually a thing.