Since Mastodon is not very flexible with regard to how it handles user permissions / authentication or additional functionalities, it would make more sense for a proof-of-concept to embed Mastodon rather than making it the UI.
Since Mastodon is not very flexible with regard to how it handles user permissions / authentication or additional functionalities, it would make more sense for a proof-of-concept to embed Mastodon rather than making it the UI.