[MC-129838] Lava is blue with vanilla datapack disabled

Lava is the wrong color when the vanilla datapack is disabled. Also you can't swim in water and cobble generation doesn't happen.

Linked issues

I'm not seeing any blue lava in the normal world or the nether. What seed are you using?

Only when you load a world with the vanilla datapack disabled..... I dont think that the texture is supposed to change from that.

It's because it's looking for the #minecraft:lava fluid tag, if that doesn't exist, this happens

Bug extant in 1.13 pre-1. It functionally means you can't disable the vanilla datapack.