I am using Mastodon and Fosstodon since a few weeks. I used to rely on a proprietary platform and so far I really enjoy Fosstodon (thanks for it).
I am working on the Elisa music player as part of the KDE project.
I am using FOSS and KDE and Debian since 2004 and a PowerPC laptop.
I'd be very surprised if not.
Fosstodon is a Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.