If this parameter is set to 'true' (default), Gigya attempts to logout the user out from all providers to which they are connected and which support this feature (currently only Facebook and SAML sessions can be forcibly logged out). Note that Facebook only allows an app to log the user out of Facebook, if the app was used to log the user in. If the user was already logged into Facebook, a 3rd party app does not have the necessary permissions to end the user's Facebook session.
If this parameter is set to 'false', the user will remain logged in to all providers after logging out from the Gigya platform, i.e., they will only be logged out of Gigya.
In order to force logout from Facebook, your Facebook app definition must have a Domain Alias (CNAME) that matches the name of your site, entered in both the "Site URL" parameter (Website section) and the "Valid OAuth redirect URI" (Security section). You must also enable native SDK capabilities in the Gigya Admin Console's Site Settings page in the Facebook Configuration dialog.