Backend Search Error

[ERAG]

Hello Community
Since update PHP from 7.4 to 8.1 the quick search in Backend has a problem and shows only the following error message:
A technical problem with the server created an error. Try again to continue what you were doing. If the problem persists, try again later.

If i enter a name it works fine, as soon as a number with at least three digits is entered the error message appears.

Does anyone have an idea what this could be?

Magento 2.4.4-p4 Community
PHP8.1
Apache 2.4
Mariadb 10.4

[theMageComp]

Hello @ERAG 

Look for any related error messages or stack traces in the Magento logs, typically located in your Magento installation's directory. Specifically, check the system.log and exception.log files for any relevant entries. This may provide more specific information about the error.

[ERAG]

Hello 

I found the following message in the system log after entering a search:

[2023-07-14T07:21:44.703050+00:00] main.ERROR: Deprecated Functionality: strip_tags(): Passing null to parameter #1 ($string) of type string is deprecated in /var/www/html/erag.swiss/public_html/vendor/magento/module-catalog-search/Model/Search/Catalog.php on line 74 [] []
[2023-07-14T07:21:44.703507+00:00] main.CRITICAL: Exception: Deprecated Functionality: strip_tags(): Passing null to parameter #1 ($string) of type string is deprecated in /var/www/html/erag.swiss/public_html/vendor/magento/module-catalog-search/Model/Search/Catalog.php on line 74 in /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/ErrorHandler.php:61
Stack trace:
#0 [internal function]: Magento\Framework\App\ErrorHandler->handler()
#1 /var/www/html/erag.swiss/public_html/vendor/magento/module-catalog-search/Model/Search/Catalog.php(74): strip_tags()
#2 /var/www/html/erag.swiss/public_html/vendor/magento/module-backend/Controller/Adminhtml/Index/GlobalSearch.php(92): Magento\CatalogSearch\Model\Search\Catalog->load()
#3 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(58): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch->execute()
#4 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->___callParent()
#5 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(153): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->Magento\Framework\Interception\{closure}()
#6 /var/www/html/erag.swiss/public_html/generated/code/Magento/Backend/Controller/Adminhtml/Index/GlobalSearch/Interceptor.php(23): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->___callPlugins()
#7 /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/Action/Action.php(111): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->execute()
#8 /var/www/html/erag.swiss/public_html/vendor/magento/module-backend/App/AbstractAction.php(151): Magento\Framework\App\Action\Action->dispatch()
#9 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(58): Magento\Backend\App\AbstractAction->dispatch()
#10 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->___callParent()
#11 /var/www/html/erag.swiss/public_html/vendor/magento/module-backend/App/Action/Plugin/Authentication.php(145): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->Magento\Framework\Interception\{closure}()
#12 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(135): Magento\Backend\App\Action\Plugin\Authentication->aroundDispatch()
#13 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(153): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->Magento\Framework\Interception\{closure}()
#14 /var/www/html/erag.swiss/public_html/generated/code/Magento/Backend/Controller/Adminhtml/Index/GlobalSearch/Interceptor.php(32): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->___callPlugins()
#15 /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/FrontController.php(245): Magento\Backend\Controller\Adminhtml\Index\GlobalSearch\Interceptor->dispatch()
#16 /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/FrontController.php(212): Magento\Framework\App\FrontController->getActionResponse()
#17 /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/FrontController.php(147): Magento\Framework\App\FrontController->processRequest()
#18 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(58): Magento\Framework\App\FrontController->dispatch()
#19 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Framework\App\FrontController\Interceptor->___callParent()
#20 /var/www/html/erag.swiss/public_html/vendor/magento/framework/Interception/Interceptor.php(153): Magento\Framework\App\FrontController\Interceptor->Magento\Framework\Interception\{closure}()
#21 /var/www/html/erag.swiss/public_html/generated/code/Magento/Framework/App/FrontController/Interceptor.php(23): Magento\Framework\App\FrontController\Interceptor->___callPlugins()
#22 /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/Http.php(116): Magento\Framework\App\FrontController\Interceptor->dispatch()
#23 /var/www/html/erag.swiss/public_html/generated/code/Magento/Framework/App/Http/Interceptor.php(23): Magento\Framework\App\Http->launch()
#24 /var/www/html/erag.swiss/public_html/vendor/magento/framework/App/Bootstrap.php(264): Magento\Framework\App\Http\Interceptor->launch()
#25 /var/www/html/erag.swiss/public_html/pub/index.php(30): Magento\Framework\App\Bootstrap->run()
#26 {main} {"report_id":"1ca2f47017e608baf04b68cd0b1557169ec09d270a4a6904d0ce1c03cff08123"} []