Fatal error: Uncaught Error: Class 'Nextend\Framework\Controller\AbstractController' not found in C:\xampp\htdocs\wp-content\plugins\smart-slider-3\Nextend\Framework\Controller\AjaxController.php:10 Stack trace: #0 {main} thrown in C:\xampp\htdocs\wp-content\plugins\smart-slider-3\Nextend\Framework\Controller\AjaxController.php on line 10