fosstodon.org is one of the many independent Mastodon servers you can use to participate in the fediverse.
Fosstodon is an invite only Mastodon instance that is open to those who are interested in technology; particularly free & open source software.
If you wish to join, contact us for an invite.
@inuit can you reach out to our Communication Team for Stickers to send to you? There we can also discuss about the shirts. https://xmpp.org/community/chat/