Fatal error: Uncaught Error: Class 'Magento\Backend\Block\Widget\Container' not found in /home/esecureh/public_html/magdemo/vendor/magento/module-cms/Block/Adminhtml/Wysiwyg/Images/Content.php:16 Stack trace: #0 {main} thrown in /home/esecureh/public_html/magdemo/vendor/magento/module-cms/Block/Adminhtml/Wysiwyg/Images/Content.php on line 16