Fatal error: Uncaught Error: Class 'AC\Column\Placeholder' not found in C:\xampp\htdocs\wp-content\plugins\admin-columns-pro\admin-columns\classes\Column\WooCommercePlaceholder.php:10 Stack trace: #0 {main} thrown in C:\xampp\htdocs\wp-content\plugins\admin-columns-pro\admin-columns\classes\Column\WooCommercePlaceholder.php on line 10