I am trying to create a custom configuration for lost cities. While doing so, I believe I have stumbled upon a bug in how biomes are picked.

The concept: A dry wasteland with very large, but rare and largely damaged cities. Also, untouched "bio domes" that can contain any single biome, preferably without any actual city generation inside. The RP backstory would be that previous inhabitants of this world, the city builders, saw the end of their world coming and built various eco domes to try and preserve the ecosystems within.

The bug: I used the "biosphere" profile as a starting point. The first thing I did was realize that I wanted more than just jungle spheres, and I don't really care what biome it is in the dome. So, I made the "S:allowedBiomeFactors" empty. This resulted in the config apparently ignoring the configuration from the bio_wasteland profile.

Bug case
profile_biospheres_custom:
S:allowedBiomeFactors < >

profile_bio_wasteland_custom:
S:allowedBiomeFactors < stone_beach=1 dead_forest=1 outback=1 volcanic_island=1 wasteland=.3 >

Expectation: Spheres of varying biome types surrounded by wasteland.
Result: Spheres of varying biome types surrounded by any biome (usually the same biome as in the sphere).

Working case
profile_biospheres_custom:
S:allowedBiomeFactors < jungle=1 jungle_hills=1 jungle_edge=2 >

profile_bio_wasteland_custom:
S:allowedBiomeFactors < stone_beach=1 dead_forest=1 outback=1 volcanic_island=1 wasteland=.3 >

expectation: Spheres of only jungle types surrounded by wasteland
result: matches expectation.