Links to ID providers
Microsoft Azure Active Directory
https://docs.microsoft.com/en-us/azure/active-directory/develop/v2-protocols-oidc
https://docs.microsoft.com/en-us/azure/active-directory/develop/v1-protocols-openid-connect-code
MS Active Directory Federation Services v4.0
https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/ff641697(v=ws.10)?redirectedfrom=MSDN
Google
https://developers.google.com/identity/protocols/oauth2
https://developers.google.com/identity/protocols/OpenIDConnect
Facebook
https://developers.facebook.com/docs/facebook-login/multiple-providers/
Twitter
https://developer.twitter.com/en/docs/basics/authentication/guides/log-in-with-twitter
LinkedIN
https://docs.microsoft.com/en-us/linkedin/shared/authentication/client-credentials-flow?context=linkedin/compliance/context
GitHub
https://help.github.com/en/github/authenticating-to-github/authorizing-oauth-apps
Okta
https://developer.okta.com/docs/api/resources/oidc
Keycloak
https://www.keycloak.org/