+CONSOLE WARNING: Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check http://xhr.spec.whatwg.org/.
CONSOLE ERROR: XMLHttpRequest cannot load http://127.0.0.1:8000/xmlhttprequest/resources/access-control-allow-lists.php?origin=http%3A%2F%2Fexample.net%2C%20http%3A%2F%2Flocalhost%3A8000. The 'Access-Control-Allow-Origin' header contains multiple values 'http://example.net, http://localhost:8000', but only one is allowed. Origin 'http://localhost:8000' is therefore not allowed access.