* can block head requests.
		 */
		$response          = wp_remote_get( $test_url, array( 'timeout' => 5 ) );
		$x_pingback_header = wp_remote_retrieve_header( $response, 'x-pingback' );
		$pretty_permalinks = $x_pingback_header && get_bloginfo( 'pingback_url' ) === $x_pingback_header;

		if ( $pretty_permalinks ) {
			return true;
		}
	}

	/*
	 * If it makes it this far, pretty permalinks failed.
	 * Fallback to query-string permalinks.
	 */
	$wp_rewrite->set_permalink_structure( '' );
	$wp_rewrite->flush_rules( true );

	return false;
}

if ( ! function_exists( 'wp_new_blog_notification' ) ) :
	/**
	 * Notifies the site admin that the installation of WordPress is complete.
	 *
	 * Sends an email to the new administrator that the installation is complete
	 * and provides them with a record of their login credentials.
	 *
	 * @since 2.1.0
	 *
	 * @param string $blog_title Site title.
	 * @param string $blog_url   Site URL.
	 * @param int    $user_id    Administrator's user ID.
	 * @param string $password   Administrator's password. Note that a placeholder message is
	 *                           usually passed instead of the actual password.
	 */
	function wp_new_blog_notification( $blog_title, $blog_url, $user_id, $password ) {
		$user      = new WP_User( $user_id );
		$email     = $user->user_email;
		$name      = $user->user_login;
		$login_url = wp_login_url();

		$message = sprintf(
			/* translators: New site notification email. 1: New site URL, 2: User login, 3: User password or password reset link, 4: Login URL. */
			__(
				'Your new WordPress site has been successfully set up at:

%1$s

You can log in to the administrator account with the following information: