Fatal error: Uncaught Error: Class "WP_Customize_Section" not found in /usr/home/AriesPB/domains/elektrobud-koszalin.pl/public_html/wp-includes/customize/class-wp-customize-sidebar-section.php:17
Stack trace:
#0 {main}
  thrown in /usr/home/AriesPB/domains/elektrobud-koszalin.pl/public_html/wp-includes/customize/class-wp-customize-sidebar-section.php on line 17