Fatal error: Uncaught Error: Call to undefined function add_action() in /home10/amoutsei/public_html/wp-content/plugins/gutenberg/lib/experimental/navigation-theme-opt-in.php:71 Stack trace: #0 {main} thrown in /home10/amoutsei/public_html/wp-content/plugins/gutenberg/lib/experimental/navigation-theme-opt-in.php on line 71