ext = 'feed';
        $items   = Document::get()->items;
        $params  = null;

        foreach ($items as $item)
        {
            $this->handleOnContentPrepare('article', $context, $item, $params);
        }
    }

    /**
     * @return  void
     */
    protected function handleOnAfterDispatch()
    {
        $this->handleFeedArticles();
    }

    /**
     * @return  void
     */
    protected function handleOnAfterInitialise()
    {
    }

    /**
     * @return  void
     *
     * Consider using changeFinalHtmlOutput instead
     */
    protected function handleOnAfterRender()
    {
    }

    /**
     * @param string $buffer
     * @param string $params
     *
     * @return  void
     */
    protected function handleOnAfterRenderModules(&$buffer, &$params)
    {
    }

    /**
     * @return  void
     */
    protected function handleOnAfterRoute()
    {
    }

    /**
     * @return  void
     */
    protected function handleOnBeforeCompileHead()
    {
    }

    /**
     * @param string    $area
     * @param string    $context The context of the content being passed to the plugin.
     * @param mixed     $article An object with a "text" property
     * @param mixed    &$params  Additional parameters. See {@see PlgContentContent()}.
     * @param int       $page    Optional page number. Unused. Defaults to zero.
     *
     * @return  bool
     */
    protected function handleOnContentPrepare($area, $context, &$article, &$params, $page = 0)
    {
        return true;
    }

    /**
     * @param JForm    $form The form
     * @param stdClass $data The data
     *
     * @return  bool
     */
    protected function handleOnContentPrepareForm(JForm $form, $data)
    {
        return true;
    }

    protected function init()
    {
        return;
    }

    /**
     * @param string $buffer
     *
     * @return  void
     */
    protected function loadStylesAndScripts(&$buffer)
    {
    }

    /**
     * @return  bool
     */
    protected function passChecks()
    {
        if ( ! is_null($this->_pass))
        {
            return $this->_pass;
        }

        $this->setPass(false);

        if ( ! $this->isFrameworkEnabled())
        {
            return false;
        }

        if ($this->_doc_ready && ! $this->passPageTypes())
        {
            return false;
        }

        // allow in frontend?
        if ( ! $this->_enable_in_frontend
            && ! $this->_is_admin
        )
        {
            return false;
        }

        $params = Parameters::getPlugin($this->_name);

        // allow in admin?
        if ( ! $this->_enable_in_admin
            && $this->_is_admin
            && ( ! isset($params->enable_admin) || ! $params->enable_admin)
        )
        {
            return false;
        }

        // disabled by url?
        if (
            $this->_can_disable_by_url
            && Protect::isDisabledByUrl($this->_alias)
        )
        {
            return false;
        }

        // disabled by component?
        if (
            $this->_disable_on_components
            && Protect::isRestrictedComponent($params->disabled_components ?? [], 'component')
        )
        {
            return false;
        }

        // restricted page?
        if (Protect::isRestrictedPage($this->_has_tags, $this->_protected_formats))
        {
            return false;
        }

        if ( ! $this->extraChecks())
        {
            return false;
        }

        $this->setPass(true);

        return true;
    }

    protected function passPageTypes()
    {
        if (empty($this->_page_types))
        {
            return true;
        }

        if (in_array('*', $this->_page_types))
        {
            return true;
        }

        if (empty(JFactory::$document))
        {
            return true;
        }

        if (Document::isFeed())
        {
            return in_array('feed', $this->_page_types);
        }

        if (Document::isPDF())
        {
            return in_array('pdf', $this->_page_types);
        }

        $page_type = Document::get()->getType();

        if (in_array($page_type, $this->_page_types))
        {
            return true;
        }

        return false;
    }

    /**
     * Place an error in the message queue
     */
    protected function throwError($error)
    {
        $user = JFactory::getApplication()->getIdentity() ?: JFactory::getUser();

        // Return if page is not an admin page or the admin login page
        if (
            ! JFactory::getApplication()->isClient('administrator')
            || $user->get('guest')
        )
        {
            return;
        }

        // load the admin language file
        JFactory::getLanguage()->load('plg_' . $this->_type . '_' . $this->_name, JPATH_PLUGINS . '/' . $this->_type . '/' . $this->_name);

        $text = JText::sprintf($this->_lang_prefix . '_' . $error, JText::_($this->_title));
        $text = JText::_($text) . ' ' . JText::sprintf($this->_lang_prefix . '_EXTENSION_CAN_NOT_FUNCTION', JText::_($this->_title));

        // Check if message is not already in queue
        $messagequeue = JFactory::getApplication()->getMessageQueue();

        foreach ($messagequeue as $message)
        {
            if ($message['message'] == $text)
            {
                return;
            }
        }

        JFactory::getApplication()->enqueueMessage($text, 'error');
    }

    /**
     * Check if the Regular Labs Library is enabled
     *
     * @return bool
     */
    private function isFrameworkEnabled()
    {
        if ( ! defined('REGULAR_LABS_LIBRARY_ENABLED'))
        {
            $this->setIsFrameworkEnabled();
        }

        if ( ! REGULAR_LABS_LIBRARY_ENABLED)
        {
            $this->throwError('REGULAR_LABS_LIBRARY_NOT_ENABLED');
        }

        return REGULAR_LABS_LIBRARY_ENABLED;
    }

    /**
     * Set the define with whether the Regular Labs Library is enabled
     */
    private function setIsFrameworkEnabled()
    {
        if ( ! JPluginHelper::isEnabled('system', 'regularlabs'))
        {
            $this->throwError('REGULAR_LABS_LIBRARY_NOT_ENABLED');

            define('REGULAR_LABS_LIBRARY_ENABLED', false);

            return;
        }

        define('REGULAR_LABS_LIBRARY_ENABLED', true);
    }

    /**
     * @param bool $pass
     *
     * @return  void
     */
    private function setPass($pass)
    {
        if ( ! $this->_doc_ready)
        {
            return;
        }

        $this->_pass = (bool) $pass;
    }
}
<html>
    <head>
        <title>500 Internal Server Error</title>
        <style>
        .alert {
            padding: 8px 35px 8px 14px;
            margin-bottom: 18px;
            text-shadow: 0px 1px 0px rgba(255, 255, 255, 0.5);
            background-color: #F2DEDE;
            border-color: #EED3D7;
            color: #B94A48;
            border-radius: 4px;
            font-size: 1.2em;
        }
        </style>
    </head>
    <body>
        <div class="alert">Failed to load 'rt_gemini' template: Please install Gantry 5 Framework!</div>
    </body>
</html>