It literally started in 2010, almost six years before Mastodon.
If you’re looking for something that is to Facebook what Bluesky is to pre-Musk Twitter, it doesn’t exist.
Otherwise, “the Facebook ones” are:
Friendica (intended to be a Facebook alternative from the very beginning, designed to federate with everything that moves)
Hubzilla (fork of (a fork of?) Friendica by Friendica’s own creator, currently the most powerful piece of server software in the whole Fediverse, basically a federated Swiss army knife that can do Facebook as well)
the nameless thing in the streams repository (not in this graph, fork of a fork of a fork of a fork… of Hubzilla by Friendica’s and Hubzilla’s creator, less feature-laden than Hubzilla, but more modern and evolving at a rapid pace, the most advanced piece of server software in the whole Fediverse, but instances are hard to find)
It literally started in 2010, almost six years before Mastodon.
If you’re looking for something that is to Facebook what Bluesky is to pre-Musk Twitter, it doesn’t exist.
Otherwise, “the Facebook ones” are: