title: Axios Doesn't Send Headers, Even The CORS Preflight Already Enabled
body: <p>Nodejss Server.js :</p>
  
  <pre><code>app.use(function(req, res, next) {
      res.header("Access-Control-Allow-Origin", "*");
      res.header("Access-Control-Request-Headers", "Origin, X-Requested-With, Content-Type, x-access-token");
      res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, x-access-token");
      res.header("Access-Control-Expose-Headers", "Origin, X-Requested-With, Content-Type, x-access-token");
      next();
  });
  </code></pre>
  
  <p>Reactjs upload :</p>
  
  <pre><code>let axiosConfig = {
      headers: {
          "Access-Control-Allow-Origin": "*",
          'crossDomain': true,
          'Content-Type': 'multipart/form-data',
          'x-access-token': Cookies.get('token')
      }
  };
  axios.post('/api/file/upload',formData, axiosConfig).then(
      response =&gt; {
          console.log(response);
      }
  ).catch(
      function(error){
      console.log(error);
  });
  </code></pre>
  
  <p>With postman, the post method works, when I try console.log(req.headers['x-access-token']); it returns the jwt token.</p>
  
  <p>But with the browser, the post method works but the headers don't send, when I try console.log(req.headers['x-access-token']); it returns undefined. So its always give 403 status response.</p>