My understanding of the docs is when `usePopup` is true, no data is posted to the redirect uri but rather the data is returned in a Promise (or DOMEvent) in the page that initiated the pop up."If the authorization flow started using the signIn function, it returns a promise that will get resolved if the authorization succeeds, or rejected if fails."(https://developer.apple.com/documentation/sign_in_with_apple/sign_in_with_apple_js/configuring_your_webpage_for_sign_in_with_apple)AppleID.auth.init(params); AppleID.auth.signIn().then((data) => { console.log(data); });