title: Messenger Extensions object only has {"AppleMusic":{}}
body: <p>I'm trying to make a messenger bot and chat extension.</p>
  
  <ol>
  <li>I set the home_url</li>
  <li>whitelisted the URL</li>
  <li>Loaded the SDK correctly</li>
  <li>doing everything inside <code>window.extAsyncInit</code></li>
  <li>And all the tests I'm doing are inside the messenger app in mobile.</li>
  </ol>
  
  <p>But when I open the chat extension normally inside a chat thread and try to use,</p>
  
  <pre><code>getContext() or any other method
  </code></pre>
  
  <p>Nothing happens.</p>
  
  <p>i.e.</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
          window.extAsyncInit = function () {
               MessengerExtensions.getContext('I pasted my app id here without quotes',
                 function success(result){
                   alert("Success: "+result.psid);
                 },
                 function error(result){
                   alert(JSON.stringify(result));
                 }
               );
           };
    &lt;/script&gt;
  </code></pre>
  
  <p>and when I try to do this,</p>
  
  <pre><code>alert(JSON.stringify(MessengerExtensions))
  </code></pre>
  
  <p>it shows</p>
  
  <pre><code>{"AppleMusic":{}}
  </code></pre>
  
  <p>what am I missing?</p>