Fatal error: Uncaught Error: Class "Magento\Theme\Model\Design\Backend\File" not found in /var/www/magento/html/generated/code/Magento/Theme/Model/Design/Backend/File/Interceptor.php:7
Stack trace:
#0 {main}
thrown in /var/www/magento/html/generated/code/Magento/Theme/Model/Design/Backend/File/Interceptor.php on line 7