Fatal error: Uncaught Error: Call to undefined function add_action() in /users/laufgruppe-lvb/www/wordpress/wp-content/plugins/eventon-tickets/includes/admin/_copy_meta_box.php:9 Stack trace: #0 /users/laufgruppe-lvb/www/wordpress/wp-content/plugins/eventon-tickets/includes/admin/_copy_meta_box.php(524): Evo_Tx_Meta_Boxes->__construct() #1 {main} thrown in /users/laufgruppe-lvb/www/wordpress/wp-content/plugins/eventon-tickets/includes/admin/_copy_meta_box.php on line 9