An anonymous tester points out that, even after grid/folder invites has been disabled via config.txt, some options relating to invites remain visible in the Preferences window -- namely, options to enable/disable desktop notifications for invite-related events. Presumably, if a certain feature is disabled at runtime such that it is not expected to be available in the application, any/all UI elements relating to exposing that functionality to the user should also be hidden or otherwise disabled so as to avoid confusion.