ModMenu asks for config screen factories early (earlier than it should IMO). So if configs are loaded too "lazily", they may be loaded after MM asks for them. This appears to be happening with Subtle Effects.
Two possible solutions:
It appears that you have a static init() method in ModConfigs, but don't actually call it. Calling it in a mod initializer may move config generation early enough.
ModMenu asks for config screen factories early (earlier than it should IMO). So if configs are loaded too "lazily", they may be loaded after MM asks for them. This appears to be happening with Subtle Effects.
Two possible solutions:
init()
method inModConfigs
, but don't actually call it. Calling it in a mod initializer may move config generation early enough.ModMenu integration problem replicated from https://github.com/fzzyhmstrs/fconfig/issues/23