WordPress at a glance
function is not described

wp_admin_headers() WP 4.9.0

Send a referrer policy header so referrers are not sent externally from administration screens.

Hooks in function
Return

Nothing (null).

Usage

wp_admin_headers();

Code of wp admin headers: wp-admin/includes/misc.php WP 5.2.2

<?php
function wp_admin_headers() {
	$policy = 'strict-origin-when-cross-origin';

	/**
	 * Filters the admin referrer policy header value.
	 *
	 * @since 4.9.0
	 * @since 4.9.5 The default value was changed to 'strict-origin-when-cross-origin'.
	 *
	 * @link https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy
	 *
	 * @param string $policy The admin referrer policy header value. Default 'strict-origin-when-cross-origin'.
	 */
	$policy = apply_filters( 'admin_referrer_policy', $policy );

	header( sprintf( 'Referrer-Policy: %s', $policy ) );
}