notification property
Web Notification options as a JSON object.
Supports Notification instance properties as defined in Web Notification API. If present, "title" and "body" fields override [google.firebase.fcm.v1.Notification.title] and [google.firebase.fcm.v1.Notification.body].
The values for Object must be JSON objects. It can consist of num,
String, bool and null as well as Map and List values.
Implementation
core.Map<core.String, core.Object?>? notification;