1. setup OAuth2 auth module
2. set PAP to org.forgerock.openam.authentication.modules.oauth2.OAuth2PostAuthnPlugin
3. OAuth2PostAuthnPlugin fails to retrieve logoutBehavior from session and throws NPE
This is because auth module is using setUserSessionProperty() which sets property value in InternalSession instead of Session object. OAuth2PostAuthnPlugin is using SSOToken which is linked to Session object so logoutBehaviour doesn't exist.