IFRAME sandbox attribute is blocking AJAX calls
I have an application ( http://localhost/MyApp ), where some of the parts are rendered through IFRAMES. These iframed parts has no business with the rest of the application's DOM, so I applied the sandbox attribute. The IFRAME is declared like this: <iframe src="/MyApp/en/html/action?id=1" sandbox="allow-forms allow-scripts" seamless="seamless"></iframe> The iframed page has a button that makes a AJAX call to the same web application, but then rather than a HTTP GET , the browser issues a HTTP OPTIONS that appears as Cancelled , and an error happens: XMLHttpRequest cannot load http://localhost