const t = { baseURI: "https://appleid.apple.com", path: "/auth/authorize", originURI: "", env: "prod", uxMode: "redirect", responseType: "code id_token", responseMode: "form_post", client: { clientId: "", scope: "", redirectURI: "", state: "" } };
Notice the responseMode which is set to form_post which I believe is the only supported mode.
This means you can no longer do things like localhost redirect_uri's for testing, or even use Apple Sign In on an internal web-app. Also, goes against OAuth2. :(
I submitted this feedback. Hopefully, someone takes a look.