WordPress at a glance
filter is not described

woocommerce_before_widget_product_review_list filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_before_widget_product_review_list', 'filter_function_name_724' );
function filter_function_name_724( $html ){
	// filter...

	return $html;
}
$html
-

Where the hook is called

WC_Widget_Recent_Reviews::widget()
woocommerce_before_widget_product_review_list
woocommerce/includes/widgets/class-wc-widget-recent-reviews.php 73
echo wp_kses_post( apply_filters( 'woocommerce_before_widget_product_review_list', '<ul class="product_list_widget">' ) );

Where in WP core the hook is used WooCommerce

Usage not found.