The relevant change is this: https://github.com/jheidecker/lemmony/commit/9b0b7232a1a942615eb67a34f2526328a23fcdd5
It's not meaningful though. It allows one to optionally limit to the top-n communities by active-user count, but the default is still unlimited and the docs still do nothing to explain the abusive load that excessive subscription puts on instances that host communities.