Hi Neemesh,
The Gluu Server makes use of a SAML login handler to push all authentications to OpenID Connect. So if someone authenticates first at a SAML site, they get both an OpenID Connect and a SAML session. If they authenticate first to an OpenID Connect site, they only get an OIDC session. However, when they hit a SAML site afterwards, the Gluu Server recognizes that they already have an OIDC session and simply provides a SAML session without authentication.
Thanks,
Will