Container Core
This mod let's you customize your containers, or support you in creating them while making compatible with the json customizations.
For example, add objects like an entity that follows your mouse anywhere in the screen, any mob, see it here:
Example
Get started:
https://github.com/dcqout/dcqinvcore/wiki
Current know (mods/resource packs) using this mod:
Vanilla Defaults: Modifies vanilla with jsons.
Fletching: Used for the Fletching table menu screen.
