By default everything lives in this browser only. To back up preferences and the app registry across devices, point mosaic at storage you own — a server on your tailnet, or your own Convex deployment. Credentials and tokens never leave this browser either way.
Nothing to configure. Data stays in this browser.
Paste an app's URL — mosaic fetches /.well-known/mosaic.json from it. Your registry lives only in this browser; the app is linked, never embedded.