title: Firebase Cloud Messaging Notification Vibration
body: <p>Is it possible to make an Android device vibrate when receiving notifications in the background with Firebase Cloud Messaging? From the <a href="https://firebase.google.com/docs/cloud-messaging/http-server-ref#notification-payload-support" rel="noreferrer">Syntax Reference</a> I have seen and tested that sound is supported, but no info on vibration. Or is it somehow possible to provide a customized implementation for this notification where I would directly set the vibration?</p>