XF 2.2 Laminas RSS Feed error showing

[WildestDrake]

Hey supporters, We're having an odd error with our RSS feeds, causing a whole bunch of errors at random intervals.

An exception occurred:

[Laminas\Stdlib\Exception\RuntimeException] No wrapper found supporting "UTF-8" in src/vendor/laminas/laminas-stdlib/src/StringUtils.php on line 134
Laminas\Stdlib\StringUtils::getWrapper() in src/vendor/laminas/laminas-feed/src/Writer/Extension/ITunes/Feed.php at line 41
Laminas\Feed\Writer\Extension\ITunes\Feed->__construct() in src/vendor/laminas/laminas-feed/src/Writer/StandaloneExtensionManager.php at line 53
Laminas\Feed\Writer\StandaloneExtensionManager->get() in src/vendor/laminas/laminas-feed/src/Writer/ExtensionManager.php at line 62
Laminas\Feed\Writer\ExtensionManager->get() in src/vendor/laminas/laminas-feed/src/Writer/AbstractFeed.php at line 897
Laminas\Feed\Writer\AbstractFeed->_loadExtensions() in src/vendor/laminas/laminas-feed/src/Writer/AbstractFeed.php at line 45
Laminas\Feed\Writer\AbstractFeed->__construct() in src/XF/Pub/View/Forum/Rss.php at line 14
XF\Pub\View\Forum\Rss->renderRss() in src/XF/Mvc/Renderer/AbstractRenderer.php at line 91
XF\Mvc\Renderer\AbstractRenderer->renderViewObject() in src/XF/Mvc/Renderer/Xml.php at line 74
XF\Mvc\Renderer\Xml->renderView() in src/XF/Mvc/Dispatcher.php at line 458
XF\Mvc\Dispatcher->renderView() in src/XF/Mvc/Dispatcher.php at line 440
XF\Mvc\Dispatcher->renderReply() in src/XF/Mvc/Dispatcher.php at line 400
XF\Mvc\Dispatcher->render() in src/XF/Mvc/Dispatcher.php at line 58
XF\Mvc\Dispatcher->run() in src/XF/App.php at line 2300
XF\App->run() in src/XF.php at line 488
XF::runApp() in index.php at line 20

It's been going on since we updated from 2.1 to 2.2

 

[WildestDrake]

It happened once we updated to PHP 7.4, and it had deactivated/uninstalled the extension "mbstring"
Once we had that re-installed it fixed itself!
Just in case anyone might have the same issue.