Fatal error: Uncaught Error: Call to undefined function is_cart() in /www/htdocs/eurospor/wp/wp-content/plugins/woocommerce-incremental-product-quantities/incremental-product-quantities.php:168 Stack trace: #0 /www/htdocs/eurospor/wp/wp-includes/class-wp-hook.php(298): Incremental_Product_Quantities->input_value_validation('') #1 /www/htdocs/eurospor/wp/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #2 /www/htdocs/eurospor/wp/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #3 /www/htdocs/eurospor/wp/wp-includes/script-loader.php(1300): do_action('wp_enqueue_scri...') #4 /www/htdocs/eurospor/wp/wp-includes/class-wp-hook.php(298): wp_enqueue_scripts('') #5 /www/htdocs/eurospor/wp/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #6 /www/htdocs/eurospor/wp/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #7 /www/htdocs/eurospor/wp/wp-includes/general-template.php(2589): do_action('wp_head') #8 /www/htdocs/eurospor/wp/wp-content/themes/storefront/header.php(18): wp_h in /www/htdocs/eurospor/wp/wp-content/plugins/woocommerce-incremental-product-quantities/incremental-product-quantities.php on line 168