lava in custom dimension

There is no way to stop that happening yet, but you could just raise the terrain, lava pools will usually only spawn very low in the world.

I already replied to this in another forum, but I'll post it here too in-case people visit here.

REPOST:

This is a fix that worked on me:

1. Go into any biome you made spawn in this dimension
2. Go in the features tab
3. Under the "Vanilla features" title it says "Default biome features", and "Caves" are selected by default
4. Click on "caves" and click delete

I think this might prevent caves from spawning in your biome, but it also gets rid of the lava, which if you are making a dimension similar to the Nether or the End, this solution will not affect anything other than fixing your lava from spawning in.