@tsyum I think they might be using ActivityPub through Peertube instead of Mastodon?(For new folks: Peertube is the equivalent of Youtube except unlike Youtube it's able to connect to anything that uses the ActivityPub protocol, like Mastodon. Kinda like how I'm posting right now to Mastodon users from Friendica which is a Facebook equivalent.)

@CathyBikesBook hey there. Just in case nobody has told you: you can follow hashtags. This will fill your timeline and you will find interesting people to follow