Fatal error: Uncaught Error: Class 'Facebook\FacebookCanvasLoginHelper' not found in /home/allfirec/public_html/facebook/facebook-php-sdk-v4-4.0-dev/src/Facebook/FacebookPageTabHelper.php:31 Stack trace: #0 {main} thrown in /home/allfirec/public_html/facebook/facebook-php-sdk-v4-4.0-dev/src/Facebook/FacebookPageTabHelper.php on line 31