Fatal error: Uncaught Error: Class 'WP_Customize_Panel' not found in D:\htdocs2\a-resultat.dk\wp-includes\customize\class-wp-customize-themes-panel.php:17 Stack trace: #0 {main} thrown in D:\htdocs2\a-resultat.dk\wp-includes\customize\class-wp-customize-themes-panel.php on line 17