So i use paperMC to have an private server, i run it vanilla because i cannot wrap my head around how to add mods like alexs caves on linux with paper as a server, so i just have FAWE
So my newly generated world ended hollow, so no blocks between ore/resource blocks.
We did not notice because there was a ravine nearby, looked pretty much normal untill i wanted to add a cellar under the house and fell into the abyss. It cool because - materials galore but it breaks the world.
How to ensure it does not happend?
I just have fawe. Nothing else.
Its really even. Everywhere its just two layers of earth blocks, then its free fall till bedrock (or some material blocks)