title: FCM doesn't work on Chrome, but works on Edge and Firefox
body: <p>I am playing with firebase web codelab example from <a href="https://codelabs.developers.google.com/codelabs/firebase-web/#0" rel="nofollow noreferrer">here</a></p>
  
  <p>Everything works when I run already "completed" lab (from the "web" directory), except one strange problem:
  I can't get FCM notifications working on Chrome (Version 80.0.3987.163 (Official Build) (64-bit)).</p>
  
  <p>It works when the same site runs in Firefox and Edge, but on Chrome it doesn't work neither locally nor deployed on firebase hosting (with https links).</p>
  
  <p>I get a request to allow notifications from the site, get a token, token is stored in db and can be seen in the console, but when I paste this token into postman - nothing happens (fcm send returns success, and fails if I pass wrong server credentials or token).
  Exactly same workflow with same postman command works on Firefox and Edge.</p>
  
  <p>As it is Google 100% code (directly cloned from <a href="https://github.com/firebase/codelab-friendlychat-web" rel="nofollow noreferrer">here</a>) I doubt the problem is with the code, and if it works for Edge and Firefox apparently all credentials are correct.</p>
  
  <p>Update:
  added relevant code samples
  from public/index.html</p>
  
  <pre><code>&lt;!-- Import and configure the Firebase SDK --&gt;
  &lt;!-- These scripts are made available when the app is served or deployed on Firebase Hosting --&gt;
  &lt;!-- If you do not want to serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup --&gt;
  &lt;script src="/__/firebase/7.14.1/firebase-app.js"&gt;&lt;/script&gt;
  &lt;script src="/__/firebase/7.14.1/firebase-auth.js"&gt;&lt;/script&gt;
  &lt;script src="/__/firebase/7.14.1/firebase-storage.js"&gt;&lt;/script&gt;
  &lt;script src="/__/firebase/7.14.1/firebase-messaging.js"&gt;&lt;/script&gt;
  &lt;script src="/__/firebase/7.14.1/firebase-firestore.js"&gt;&lt;/script&gt;
  &lt;script src="/__/firebase/7.14.1/firebase-performance.js"&gt;&lt;/script&gt;
  &lt;script src="/__/firebase/init.js"&gt;&lt;/script&gt;
  
  &lt;script src="scripts/main.js"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>from public/firebase-messaging-sw.js</p>
  
  <pre><code>// Import and configure the Firebase SDK
  // These scripts are made available when the app is served or deployed on Firebase Hosting
  // If you do not want to serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup
  importScripts('/__/firebase/7.14.1/firebase-app.js');
  importScripts('/__/firebase/7.14.1/firebase-messaging.js');
  importScripts('/__/firebase/init.js');
  
  firebase.messaging();
  </code></pre>
  
  <p>Postman request:</p>
  
  <pre><code>{
  "notification": {
  "title": "New chat message!",
  "body": "There is a new message in FriendlyChat",
  "icon": "/images/profile_placeholder.png",
  "click_action": "http://localhost:5000"
  },
  "to":"cjXXXXXXXm9l"
  }
  </code></pre>
  
  <p>Response to postman request:</p>
  
  <pre><code>{
  "multicast_id": 7762212940520416194,
  "success": 1,
  "failure": 0,
  "canonical_ids": 0,
  "results": [
      {
          "message_id": "0:1587665587020317%e609af1cf9fd7ecd"
      }
  ]
  }
  </code></pre>
  
  <p>Anybody has any idea what it can be?</p>