@heluecht asked them about implementing @forgefed
"The current specs I proposed are meant to allow people on the fediverse to follow activity on Gitlab instances, without write access, as a first step toward the fediverse. For that reason, I prefer to avoid using an extension of ActivityPub : if I do use it, then Mastodon, Lemmy and others now have to implement support for that extension too, or the content we send to them will be useless."