title: Browser issue for firebase cloud messging
body: <p>using firebase messaging.It works on chrome, firefox but not working on Microsoft edge and safari browser.</p>
  
  <blockquote>
    <p>The error raised in the console is : <strong>FirebaseError: Messaging: This browser doesn't support the API's required to use the firebase SDK. (messaging/unsupported-browser).</strong></p>
  </blockquote>
  
  <p>what i'm getting wrong code is:</p>
  
  <pre><code>var config = {
    apiKey: "xxx",
    authDomain: "xxx.firebaseapp.com",
    databaseURL: "https://xxx.firebaseio.com",
    projectId: "xxx",
    storageBucket: "xx.appspot.com",
    messagingSenderId: "xxxxx"
  };
  firebase.initializeApp(config);
  const messaging = firebase.messaging();
  messaging.onMessage(function(payload){
  var resp = JSON.parse(payload.data.notification);
  var board_id = resp.boardId;
    var notificationTitle = resp.title;
    var notificationOptions = {
      body: resp.body,
      icon: resp.icon
    };})
  </code></pre>