title: Session cookie not sending with XHR requests
body: <p>My react app (from domain react-app.com) is loaded inside a website beautiful-site.com and the requests sending from react app doesn't sending the session cookie associated with it.</p>
  
  <p>The workaround I had was added the below header in server and in react app XHR requests sent with <code>withCredentials: true</code></p>
  
  <pre><code>Access-Control-Allow-Origin: https://beautiful-site.com
  Access-Control-Allow-Credentials: true
  </code></pre>
  
  <p>The issue is I can specify a particular site in <code>Access-Control-Allow-Origin</code>, because the react app will be added to many sites not one.</p>
  
  <p>Is there any way to get the session cookie send from react app?</p>