title: React Native: Disable sound/vibration on push notification
body: <p>I'm sending push notifications from server to clients via google FCM. </p>
  
  <p>In the react-native app I've registered these listeners: </p>
  
  <pre><code>this.notificationOpenedListener = firebase.notifications().onNotificationOpened(async (notificationOpen) =&gt; {
  
  })
  
  this.notificationListener = firebase.notifications().onNotification(async (notification) =&gt; {
  
  });
  </code></pre>
  
  <p>the <code>notification</code> data contains information if there should be a sound / vibration or not when the notification is received.</p>
  
  <p>However, I can't find any documentation about completely disabling sound/vibration on demand. </p>
  
  <p>How can I achieve this? </p>
  
  <p>UPDATE</p>
  
  <p>I've tried setting sound to an empty string on server side, but there's still sound/vibration on notification. </p>
  
  <pre><code>  var message = {
      data: {
        userId: fromUserId,
      },
      notification: {
        title: `My notifcation`,
        body: `Body`,
        sound: "",
      },
    }
  
    return sendToTopic(topicId, message)
  </code></pre>