Migrating and Upgrading to Joomla! 4.x • Joomla 4 update and site doesn´t work anymore

Hi!
Can someone help me and give me an idiot-proof instructions how to fix a website?
I updated to Joomla 4 and now site gives me an error:
"0 - Class "JString" not found"

After error reporting I got this:
Call stack
# Function Location
1 () JROOT/plugins/content/loadformmaker/loadformmaker.php:71
2 plgContentLoadformmaker->onContentPrepare() JROOT/libraries/src/Plugin/CMSPlugin.php:289
3 Joomla\CMS\Plugin\CMSPlugin->Joomla\CMS\Plugin\{closure}() JROOT/libraries/vendor/joomla/event/src/Dispatcher.php:486
4 Joomla\Event\Dispatcher->dispatch() JROOT/libraries/src/Application/EventAware.php:111
5 Joomla\CMS\Application\WebApplication->triggerEvent() JROOT/components/com_content/src/View/Featured/HtmlView.php:159
6 Joomla\Component\Content\Site\View\Featured\HtmlView->display() JROOT/libraries/src/MVC/Controller/BaseController.php:660
7 Joomla\CMS\MVC\Controller\BaseController->display() JROOT/components/com_content/src/Controller/DisplayController.php:121
8 Joomla\Component\Content\Site\Controller\DisplayController->display() JROOT/libraries/src/MVC/Controller/BaseController.php:693
9 Joomla\CMS\MVC\Controller\BaseController->execute() JROOT/libraries/src/Dispatcher/ComponentDispatcher.php:143
10 Joomla\CMS\Dispatcher\ComponentDispatcher->dispatch() JROOT/components/com_content/src/Dispatcher/Dispatcher.php:56
11 Joomla\Component\Content\Site\Dispatcher\Dispatcher->dispatch() JROOT/libraries/src/Component/ComponentHelper.php:361
12 Joomla\CMS\Component\ComponentHelper::renderComponent() JROOT/libraries/src/Application/SiteApplication.php:208
13 Joomla\CMS\Application\SiteApplication->dispatch() JROOT/libraries/src/Application/SiteApplication.php:249
14 Joomla\CMS\Application\SiteApplication->doExecute() JROOT/libraries/src/Application/CMSApplication.php:293
15 Joomla\CMS\Application\CMSApplication->execute() JROOT/includes/app.php:61
16 require_once() JROOT/index.php:32


What does this mean and what do I need to do to fix it?

Statistics: Posted by evie_123 — Sat Jan 11, 2025 2:50 pm

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