This is an issue with a proposed fix:

I've been using Treasure2 with the Twilight Forest mod, and for the most part it works really well. I have however noticed that sometimes chests generate in strange places, like the side walls of lich towers and the final castle. I assume the same issue could occur in other modded dimensions.

Suggestion: add a config option for either setting a max Y value for chest generation, or a min/max depth value like in the 1.16+ version.