public function onParse($finalText)
    {
        // if a specific post-parse function was defined, it is called
        /** @var callable $func */
        $func = $this->getParam('postParseFunction');
        if (isset($func))
            $finalText = $func($finalText);
        // add footnotes' content if needed
        if ($this->getParam('addFootnotes')) {
            $footnotes = $this->getFootnotes();
            if (!empty($footnotes))
                $finalText .= "\n" . $footnotes;
        }
        return ($finalText);
    }