Mozilla’s Hubs offering has been kicking around for several years now. Lucas described a 2018 preview of the service thusly, “It’s not Second Life, or even Facebook Spaces; it’s pretty low-key. You’re just a humble robot hanging with other robots who are hopefully your friends.”
The service has expanded features since then (including the arrival of non-robot avatars), but the bare-bones Second Life vibe is still very much intact. Mozilla notes that over the years, Hubs has hosted a number of different gatherings, from virtual events and classrooms to art galleries.