I spent the past couple of weeks building a web app that would help me find my Twitter contacts on Mastodon (and other ActivityPub-compatible sites).
I wanted it to be simple and clear, as well as to try out Astro and the React95.io design system.
The result isn't perfect, but it's as thorough as I wanted it to be to show others and gather feedback.
The code is also open source https://github.com/WesSouza/mastodon-flock (although I just realized I never fixed the README lol)