After installing you wont be able to downgrade

ReWorld will now completely take advantage of the new 1.13 item api. If you are still using 1.12 or below, you are completely fine since it will automatically adapt to that. All item ids and datas will be automatically converted to our new 1.13 item names to ensure full compatibility for newer versions of Minecraft.

Noticeable Changes:
- You can now use 1.13 Items in the StyleFile
- Stylefile now uses Item Names instead of ItemId:ItemData