https://www.rfc-editor.org/rfc/rfc6749 https://indieauth.spec.indieweb.org/
https://indieweb.org/IndieAuth https://aaronparecki.com/2018/07/07/7/oauth-for-the-open-web https://aaronparecki.com/2020/12/03/1/indieauth-2020 https://www.oauth.com/oauth2-servers/signing-in-with-google/getting-an-id-token/ https://www.oauth.com/oauth2-servers/indieauth/
https://indieweb.org/authorization-endpoint https://indieweb.org/token-endpoint
https://github.com/iamspruce/spruce-indieLogin https://github.com/nilsnh/cellar-door