Land Rover Discovery 3/4 owners’ forum.
Aside from some Facebook groups, only one - Macrumors. Which is nothing to do with Fleetwood Mac...
I haven't visited it much recently, but I am a member of the snowheads forum (dedicated to snow sports, not drugs ).
I was a member of and moderator on the Supercell forum (a mobile games company) until that was closed down in favour of the company using other forms of social media.
@Accy cyclist 's onlyfans group.