Is it possible to extend user resource in user collection with custom properties, e.g. we would like to add
token property (string type) to the user resource in order to send notifications to the user device. Maybe later on, we would like to add/extend with some additional property as well like some user settings.
The user object has a customProperties attribute that you can use for storing your custom attributes within it.
This attribute is actually not listed for some reason within the request body, but the response sample of the linked API does list it: