This parameter specifies the predefined, user-visible key-value pairs of the notification payload. See Notification payload support for detail. For more information about notification message and data message options, see Payload: https://firebase.google.com/docs/cloud-messaging/concept-options#notifications_and_data_messages
See Implementation
This parameter specifies the predefined, user-visible key-value pairs of the notification payload. See Notification payload support for detail. For more information about notification message and data message options, see Payload: https://firebase.google.com/docs/cloud-messaging/concept-options#notifications_and_data_messages