Fatal error: Uncaught Error: Class "kartik\base\Widget" not found in /var/www/html/prod/vendor/kartik-v/yii2-widget-spinner/src/Spinner.php:24 Stack trace: #0 {main} thrown in /var/www/html/prod/vendor/kartik-v/yii2-widget-spinner/src/Spinner.php on line 24