You can enable member login and chat services by generating a JWT token (for chat or analytics purposes) in Saucelive and passing it to the Saucelive Player as a query string.
After successful login, redirect the user to the address received via returnUrl, appending the server-generated JWT token as a query string, as shown below.
https://player.sauceflex.com/broadcast/{Broadcastadress}?accessToken={JWT_Token}