> Shibboleth is the last major IdP I know if that is SAML-only
Shibboleth has officially supported Plugins for OIDC for some time now.
As others said, Shiboleth is still rather pupular at Universities and higher Education, OIDC will have a hard time to set foot there without the OpenID Connect Federation Draft beeing finished and then Implemented by the different Metadata Federation that exist (most National Research Networks manage one)
Shibboleth has officially supported Plugins for OIDC for some time now.
As others said, Shiboleth is still rather pupular at Universities and higher Education, OIDC will have a hard time to set foot there without the OpenID Connect Federation Draft beeing finished and then Implemented by the different Metadata Federation that exist (most National Research Networks manage one)