I am unable to add media to a page. I click the button on the page edit page and nothing happens. The web console of firefox says "TypeError: wp.Uploader is undefined". I already tried deactivating installed plug-ins and I set the default theme ("Twenty Fourteen"). I googled this problem and I only find people who are developing their own plug-ins who have this problem. :(
TypeError: wp.Uploader is undefined error is coming, because wp media editor file is not included. Please check for this.
Basically you need to open your “wp-config.php” file in the root of your WordPress Install. Search for this line: require_once(ABSPATH . 'wp-settings.php'); And just before it add this code: define('CONCATENATE_SCRIPTS', false); Now your WordPress Install should be fixed!