Fatal error: Uncaught Error: Using $this when not in object context in /var/www/magento/html/app/code/MGS/Lookbook/view/adminhtml/templates/category.phtml:1 Stack trace: #0 {main} thrown in /var/www/magento/html/app/code/MGS/Lookbook/view/adminhtml/templates/category.phtml on line 1