@mray oof I think that's unexposed in the main branch right now..
the basic concept is that you can pre-configure various settings through the url, this is used both for an embed (iframe) and obs (browser plugin) to get the right state without interaction. There really has to be GUI to generate those, but as an example here's how the iframe I integrated into owncast works https://github.com/f0x52/owncast/blob/develop/webroot/js/app.js#L746
viewable at https://stream.pixie.town