When reviewing the OIDC Protocol spec here there is a section on ‘Initiating Login from a Third Party’ which could allow an Identity Provider (IdP) to signal to a Service Provider (SP) that a new login request should be initiated. However, when reviewing Auth0 documentation this strategy doesn’t seem to be mentioned. Does Auth0 support the OIDC Protocol spec related to 3rd Party Logins?
Though this use case is technically a part of the OIDC spec, Auth0 currently does not support 3rd Party logins with the OIDC protocol. The closest supported option would be configuring IdP-Initiated SSO with a SAML Connection instead. Please feel free to open a Feature Request on the Community site so Auth0 Product Managers can gauge interest in this particular feature.