SMillerNL

Since it’s Firefox based, do they even have the option to release their software with GPL components?

No, they invented mastodon. Which is the thing they’re adjusting.

They didn’t invent HTTP either, which they’re not claiming ownership of by using it in mastodon.

I don’t think it’s too much for the company that makes mastodon to claim mastodon is “it’s decentralised social network”. The way I read it they don’t claim ownership, they claim to be the author.