Fatal error: Uncaught Error: Class 'Magento\Indexer\Controller\Adminhtml\Indexer' not found in /home/esecureh/public_html/magdemo/vendor/magento/module-indexer/Controller/Adminhtml/Indexer/MassOnTheFly.php:14 Stack trace: #0 {main} thrown in /home/esecureh/public_html/magdemo/vendor/magento/module-indexer/Controller/Adminhtml/Indexer/MassOnTheFly.php on line 14