WP_Customize_Manager::set_preview_url( string $preview_url )

Source

File: wp-includes/class-wp-customize-manager.php

public function set_preview_url( $preview_url ) {
		$preview_url       = esc_url_raw( $preview_url );
		$this->preview_url = wp_validate_redirect( $preview_url, home_url( '/' ) );
	}