[keycloak-user] Logout in broker mode doesn't propagate session's termination

I was testing single logout in broker mode and came around this logical, but not exactly desirable behaviour, when session on the broker and session on the external idp states are not linked between the idp's. My setup is broker saml example provided with keycloak, but instead of an actual application i log in to the broker using "/account" url. Should be all the same, since it's just another web-app, protected by this realm. The behaviour is as follows: If i kill a session on the external keycloak idp, the user is not logged out. I assume since local session is alive and well the token is not being revoked. If i kill a session on the broker keycloak, upon hitting f5 user is redirected to the broker login page, but when i press external idp login button, he's logged right back with no credentials asked. I guess since the session between 2 idp's is still up, broker thinks this user is already authenticated. I tested both oidc and saml, tried different backchannel/frontchannel toggles in the UI of both broker and external IDP, but this had no visible effect. Can you please clarify if the behaviour observed is expected and normal, or did i miss some configuration steps?