GET /{user-id}/picture
requests made by apps in Development mode using either (1) a Client access token or (2) tokenless requests on an App-Scoped User ID will receive a silhouette image instead of the app user's profile image in response.GET /{user-id}/picture
tokenless requests on App-Scoped User IDs made by apps that are inactive or that have not completed Data Use Checkup will receive an error code in response.