Fatal error: Uncaught Error: Call to undefined function is_product_category() in /homepages/26/d614901684/htdocs/app614901992/wp-content/plugins/category-collapser-for-woocommerce-seo/includes/main.php:38 Stack trace: #0 /homepages/26/d614901684/htdocs/app614901992/wp-includes/class-wp-hook.php(292): conditional_functions('') #1 /homepages/26/d614901684/htdocs/app614901992/wp-includes/class-wp-hook.php(316): WP_Hook->apply_filters(NULL, Array) #2 /homepages/26/d614901684/htdocs/app614901992/wp-includes/plugin.php(484): WP_Hook->do_action(Array) #3 /homepages/26/d614901684/htdocs/app614901992/wp-includes/template-loader.php(13): do_action('template_redire...') #4 /homepages/26/d614901684/htdocs/app614901992/wp-blog-header.php(19): require_once('/homepages/26/d...') #5 /homepages/26/d614901684/htdocs/app614901992/index.php(17): require('/homepages/26/d...') #6 {main} thrown in /homepages/26/d614901684/htdocs/app614901992/wp-content/plugins/category-collapser-for-woocommerce-seo/includes/main.php on line 38