Fatal error: Uncaught Error: Attempt to modify property "classes" on null in /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-content/themes/dubline/inc/functions/theme-setup.php:109 Stack trace: #0 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/class-wp-hook.php(324): nav_menu_add_classes() #1 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/plugin.php(205): WP_Hook->apply_filters() #2 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/nav-menu-template.php(234): apply_filters() #3 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-content/themes/dubline/header.php(120): wp_nav_menu() #4 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/template.php(810): require_once('...') #5 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/template.php(745): load_template() #6 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/general-template.php(48): locate_template() #7 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-content/themes/dubline/templates/faq.php(11): get_header() #8 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-includes/template-loader.php(106): include('...') #9 /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-blog-header.php(19): require_once('...') #10 /home/dublineweb/domains/webdev.dubline.nl/public_html/index.php(17): require('...') #11 {main} thrown in /home/dublineweb/domains/webdev.dubline.nl/public_html/wp-content/themes/dubline/inc/functions/theme-setup.php on line 109