Authentik, Kubernetes and PG Admin
Authentik configuration should follow this link.
Authentik configuration should follow this link.

The provider (Oauth2) should be:

The externalsecret.yaml file should contain:

Make note that the slug from the Authentik configuration should be the same as the one in OAUTH2_SERVER_METADATA_URL. Otherwise, you'll get a 40x error.
HTH,