I've setup an OIDC Connect App inside my OneLogin account and was already able to login different users using this client
https://github.com/IdentityModel/oidc-client-js
and the "implicit flow".
The oidc-client-js supports session management out of the box using the iFrame mechanic to poll the IDP (onelogin in my case) about the status of the users session.
https://brockallen.com/2016/08/12/check-session-support-in-oidc-client-js/
The OIDC client does not even start doing so since in my signin return data there is no "session_state" value, instead it is just undefined.
I was reading the OIDC specs about it
https://openid.net/specs/openid-connect-session-1_0.html
and from paragraph 2-5 there are all the things the IDP needs to offer in order to make session management work via OIDC.
Since I could not find anything in the OneLogin Docs, I would appreciate any hint, help, experiences with this specific
https://openid.net/specs/openid-connect-session-1_0.html:
2.1. OpenID Provider Discovery Metadata
These OpenID Provider Metadata parameters MUST be included in the Server's discovery responses when Session Management and Discovery are supported:
check_session_iframe ...
end_session_endpoint ...
I don't see these metadata parameters in the OneLogin discovery metadata, so it looks like Session Management is not supported.