Fatal error: Uncaught Error: Call to undefined function add_action() in /home/theinsightpartne/public_html/blog/wp-content/plugins/gutenberg/lib/experimental/navigation-theme-opt-in.php:69 Stack trace: #0 {main} thrown in /home/theinsightpartne/public_html/blog/wp-content/plugins/gutenberg/lib/experimental/navigation-theme-opt-in.php on line 69