Fatal error: Uncaught Error: Call to undefined function add_action() in /home/kacperg/public_html/kacpergr/wp-content/plugins/colorlib-404-customizer/includes/class-cnfp-customizer.php:9 Stack trace: #0 /home/kacperg/public_html/kacpergr/wp-content/plugins/colorlib-404-customizer/includes/class-cnfp-customizer.php(513): CNFP_Customizer->__construct() #1 {main} thrown in /home/kacperg/public_html/kacpergr/wp-content/plugins/colorlib-404-customizer/includes/class-cnfp-customizer.php on line 9