If you call the end session endpoint with the id_token hint, you will invalidate the session, but the RP applications won't get a notification that the session is ended. The [Front Channel Logout Spec](http://openid.net/specs/openid-connect-frontchannel-1_0.html) works by rendering iFrames for with the logout URL for each application so that local application sessions in the browser can be ended (not just the OP session). Also, keep in mind that if the browser blocks third party cookies, logout may be broken all together. There are many articles on the Internet about the phenomemnon. Basically, logout is a dicey proposition... Perhaps one way to handle it is to make your apps use the refresh token more frequently to obtain a new access token to make sure the session is still active.