Fatal error: Uncaught Facebook\Exceptions\FacebookSDKException: Required "app_id" key not supplied in config and could not find fallback environment variable "FACEBOOK_APP_ID" in /web/htdocs/www.melfi.it/home/z/Facebook/Facebook.php:139 Stack trace: #0 /web/htdocs/www.melfi.it/home/z/fblogin.php(22): Facebook\Facebook->__construct() #1 {main} thrown in /web/htdocs/www.melfi.it/home/z/Facebook/Facebook.php on line 139