final protected function getOpenGraph($data_only = false)
    {
        $og_stack = $this->page->og->getTags();

        if ($data_only) {
            return $og_stack;
        }

        $html = '';

        foreach ($og_stack as $property => $content) {
            $html .= '<meta property="' . $property . '" content="' . $content . '">' . PHP_EOL;
        }

        return $html;
    }