The config contains system wide settings. In the following we explain some important settings which you most likely need to configure.
mail_register_bodyIf a new user registers through the consumer app he receives an activation mail. Through this setting you can configure the text and adjust the activtaion url
recaptcha_secretIf provided the consumer registration can show an google recaptcha which prevents automatic registration. You also have to provide the recaptcha public key to the consumer app
scopes_defaultThose are the scopes which are assigned by default if a new user registers
provider_google_secretIf provided a user can login through those remote providers. You also have to provide the app key to the consumer app