Fatal error: Uncaught Error: Call to undefined function add_action() in /home/kacperg/public_html/kacpergr/wp-content/plugins/jetpack/_inc/jetpack-server-sandbox.php:63 Stack trace: #0 {main} thrown in /home/kacperg/public_html/kacpergr/wp-content/plugins/jetpack/_inc/jetpack-server-sandbox.php on line 63