WordPress at a glance
function is not described

WP_Customize_Manager::get_allowed_urls() public WP 4.7.0

Get URLs allowed to be previewed.

If the front end and the admin are served from the same domain, load the preview over ssl if the Customizer is being loaded over ssl. This avoids insecure content warnings. This is not attempted if the admin and front end are on different domains to avoid the case where the front end doesn't have ssl certs. Domain mapping plugins can allow other urls in these conditions using the customize_allowed_urls filter.

{} It's a method of the class: WP_Customize_Manager{}

Hooks from the method
Return

Array. Allowed URLs.

Usage

$WP_Customize_Manager = new WP_Customize_Manager();
$WP_Customize_Manager->get_allowed_urls();

Changelog

Since 4.7.0 Introduced.

Code of WP_Customize_Manager::get_allowed_urls() WP 5.7.2

<?php
public function get_allowed_urls() {
	$allowed_urls = array( home_url( '/' ) );

	if ( is_ssl() && ! $this->is_cross_domain() ) {
		$allowed_urls[] = home_url( '/', 'https' );
	}

	/**
	 * Filters the list of URLs allowed to be clicked and followed in the Customizer preview.
	 *
	 * @since 3.4.0
	 *
	 * @param string[] $allowed_urls An array of allowed URLs.
	 */
	$allowed_urls = array_unique( apply_filters( 'customize_allowed_urls', $allowed_urls ) );

	return $allowed_urls;
}