WordPress at a glance
filter is not described

woocommerce_enable_deprecated_additional_flat_rates filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_enable_deprecated_additional_flat_rates', 'filter_function_name_9101' );
function filter_function_name_9101( $option ){
	// filter...

	return $option;
}
$option
-

Where the hook is called

In file: /includes/shipping/legacy-flat-rate/includes/settings-flat-rate.php
woocommerce_enable_deprecated_additional_flat_rates
woocommerce/includes/shipping/legacy-flat-rate/includes/settings-flat-rate.php 116
if ( apply_filters( 'woocommerce_enable_deprecated_additional_flat_rates', $this->get_option( 'options', false ) ) ) {

Where in WP core the hook is used WooCommerce

Usage not found.