phpbb\install\helper\iohandler\iohandler_base::add_error_message PHP Method

    public function add_error_message($error_title, $error_description = false)
    {
        if (!is_array($error_title) && strpos($error_title, '<br />') !== false) {
            $error_title = strip_tags(htmlspecialchars_decode($error_title));
        }
        $this->errors[] = $this->translate_message($error_title, $error_description);
    }