Looking for logging into the Oauth2 Additional Fields site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Oauth2 Additional Fields site. After that you can login as usual with your login credentials.
https://www.baeldung.com/spring-security-extra-login-fields
https://stackoverflow.com/questions/28152304/oauth-2-endpoint-additional-fields
https://github.com/laravel/passport/issues/81
https://256stuff.com/gray/docs/oauth2.0/
https://www.smashingmagazine.com/2017/05/oauth2-logging-in-facebook/
https://developer.okta.com/authentication-guide/implementing-authentication/set-up-authz-server
https://developers.google.com/identity/protocols/OpenIDConnect
https://blog.couchbase.com/spring-security-oauth2_authentication/
https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow/
https://www.callicoder.com/spring-boot-security-oauth2-social-login-part-1/
https://docs.moodle.org/dev/OAuth_2_API
https://docs.moodle.org/en/OAuth_2_authentication
https://developers.facebook.com/docs/facebook-login/