saguaros
this is the error log, thanks!
Undefined constant "T4\Helper\T4PATH_BASE"
/var/www/2you/plugins/system/t4/src/t4/Helper/Asset.php:37
Call stack
Function Location
1 () JROOT/plugins/system/t4/src/t4/Helper/Asset.php:37
2 T4\Helper\Asset::init() JROOT/plugins/system/t4/src/t4/Document/Template.php:35
3 T4\Document\Template->__construct() JROOT/plugins/system/t4/src/t4/Document/Template.php:80
4 T4\Document\Template::getInstance() JROOT/plugins/system/t4/src/t4/T4.php:132
5 T4\T4->setDocument() JROOT/plugins/system/t4/src/t4/T4.php:21
6 T4\T4::getInstance() JROOT/plugins/system/t4/src/t4/T4.php:213
7 T4\T4::render() JROOT/templates/t4_bs5_blank/component.php:11
8 require() JROOT/libraries/src/Document/HtmlDocument.php:741
9 Joomla\CMS\Document\HtmlDocument->loadTemplate() JROOT/libraries/src/Document/HtmlDocument.php:796
10 Joomla\CMS\Document\HtmlDocument->fetchTemplate() JROOT/libraries/src/Document/HtmlDocument.php:613
11 Joomla\CMS\Document\HtmlDocument->parse() JROOT/plugins/system/regularlabs/src/Application.php:65
12 RegularLabs\Plugin\System\RegularLabs\Application->render() JROOT/plugins/system/regularlabs/src/QuickPage.php:69
13 RegularLabs\Plugin\System\RegularLabs\QuickPage::getHtml() JROOT/plugins/system/regularlabs/src/QuickPage.php:49
14 RegularLabs\Plugin\System\RegularLabs\QuickPage::render() JROOT/plugins/system/regularlabs/regularlabs.php:93
15 PlgSystemRegularLabs->onAfterRoute() JROOT/libraries/src/Plugin/CMSPlugin.php:284
16 Joomla\CMS\Plugin\CMSPlugin->Joomla\CMS\Plugin{closure}() JROOT/libraries/vendor/joomla/event/src/Dispatcher.php:486
17 Joomla\Event\Dispatcher->dispatch() JROOT/libraries/src/Application/EventAware.php:111
18 Joomla\CMS\Application\WebApplication->triggerEvent() JROOT/libraries/src/Application/SiteApplication.php:790
19 Joomla\CMS\Application\SiteApplication->route() JROOT/libraries/src/Application/SiteApplication.php:232
20 Joomla\CMS\Application\SiteApplication->doExecute() JROOT/libraries/src/Application/CMSApplication.php:293
21 Joomla\CMS\Application\CMSApplication->execute() JROOT/includes/app.php:61
22 require_once() JROOT/index.php:32