Jetpack_Subscriptions::validate_settings PHP Method

    function validate_settings($settings)
    {
        global $allowedposttags;
        $default = $this->get_default_settings();
        // Blog Follow
        $settings['invitation'] = trim(wp_kses($settings['invitation'], $allowedposttags));
        if (empty($settings['invitation'])) {
            $settings['invitation'] = $default['invitation'];
        }
        // Comments Follow (single post)
        $settings['comment_follow'] = trim(wp_kses($settings['comment_follow'], $allowedposttags));
        if (empty($settings['comment_follow'])) {
            $settings['comment_follow'] = $default['comment_follow'];
        }
        return $settings;
    }