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filter is not described

wp_resource_hints filter-hook . WP 4.6.0

Filters domains and URLs for resource hints of relation type.

Usage

add_filter( 'wp_resource_hints', 'filter_function_name_2031', 10, 2 );
function filter_function_name_2031( $urls, $relation_type ){
	// filter...

	return $urls;
}
$urls(array)
URLs to print for resource hints.
$relation_type(string)
The relation type the URLs are printed for, e.g. 'preconnect' or 'prerender'.

Where the hook is called

wp_resource_hints()
wp_resource_hints
wp-includes/general-template.php 2919
$urls = apply_filters( 'wp_resource_hints', $urls, $relation_type );

Where the hook is used (in WP core)

Does not used.