The full policy is at https://danstudio.dev/privacy. In short:

• The extension sends video frames and player state only to the You Controller plugin on your own computer (ws://127.0.0.1:28443). Nothing you watch leaves your machine.
• A licence key, when you enter one or a trial starts, is checked with https://danstudio.dev/api/verify, together with a device id, so that a key works on one computer at a time.
• Usage reports (feature use and error reports, with nothing that names you) go to Google Analytics 4 and danstudio.dev only if you allow "technical and interaction data" in Firefox; they are off otherwise, and can also be switched off in the extension's settings.
• No ads, no record of the pages you visit, nothing sold or shared.