title: $.ajax call doesn't set cookies with crossDomain and xhrFields.withCredentials set true
body: <p>I'm trying to make an ajax request call from a jquery script to a cross domain server. I did include the options <code>crossDomain: true, xhrFields: { withCredentials: true }</code> to the ajax call. The server is set up with cors (<code>{origin: RegExp('\w*.mydomain.com'), credentials: true}</code>). But somehow the ajax request doesn't set the session cookie in the request. Any ideas?</p>
  
  <p><a href="https://i.stack.imgur.com/WBPPI.png" rel="nofollow noreferrer">Cookie</a></p>
  
  <p><a href="https://i.stack.imgur.com/8tiFX.png" rel="nofollow noreferrer">Options Request</a></p>
  
  <p><a href="https://i.stack.imgur.com/rDM2v.png" rel="nofollow noreferrer">Request</a></p>