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action is not described

wp_delete_site action-hook . WP 5.1.0

Fires once a site has been deleted from the database.

Usage

add_action( 'wp_delete_site', 'action_function_name_2608' );
function action_function_name_2608( $old_site ){
	// action...
}
$old_site(WP_Site)
Deleted site object.

Where the hook is called

wp_delete_site()
wp_delete_site
wp-includes/ms-site.php 266
do_action( 'wp_delete_site', $old_site );

Where the hook is used (in WP core)

wp-includes/ms-default-filters.php 46
add_action( 'wp_delete_site', 'wp_maybe_update_network_site_counts_on_update', 10, 1 );