title: Fetch Request Not Working
body: <p>I am trying to add a custom header, <code>X-Query-Key</code>, to a HTTP request using <a href="https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API" rel="nofollow">Fetch API</a> or <a href="https://www.npmjs.com/package/request" rel="nofollow">request</a> but when I add this to the header of the request it appears to fail at setting the headers and the <code>Request Method</code> is set to <code>OPTIONS</code> for some reason. </p>
  
  <p>When I remove the header it goes back to being <code>GET</code> as it should do.</p>
  
  <p>Sample code looks like below:</p>
  
  <pre><code>   const options = {
      url: url,
      headers: {
        'Accept': 'application/json',
        'X-Query-Key': '123456' //Adding this breaks the request
      }
    };
  
    return request(options, (err, res, body) =&gt; {
      console.log(body);
    });
  </code></pre>