Versions used:

• Forge 2255
• Quark r1.2-85
• Actually Additions 1.11.2-r103

Some screenshot of what happens, almost every single time:

Probably happens on other UB, but those are the two I found so far. As a note, that's using ATG generation (1.11.2-2.0.1). Will check on default generation and see how it behaves there.

Ok, seems like the same happens on Default worlds, so probably not ATG's fault.

The Forest UB seems to cause an overflow of leave on the cave, apparently:

Some seem to class less, like desert ones:

Forgot to take a screenshot, but the glowing grass ones also seem to work ok (grass is replaced, which makes sense, and nothing more).

This also seems to happen on oceans, both default and ATG: the gravel at the bottom is replaced with prismarine; should I put this on a separate issue maybe?