Fatal error: Uncaught Error: Class 'yii\helpers\StringHelper' not found in /var/www/html/panel-administracion/vendor/bmsrox/yii-adminlte-crud-template/controller.php:13 Stack trace: #0 {main} thrown in /var/www/html/panel-administracion/vendor/bmsrox/yii-adminlte-crud-template/controller.php on line 13