Check for null parent_entity_type_id src/Entity/LinkCheckerLink.php

This code makes sense and all, but seems strange how you would find yourself in such a situation.

Would at least need steps to reproduce, and ideally a test as well

Possibly due to the use of the filebrowser module.

I am also seeing a similar issue during cron runs:

TypeError: Drupal\linkchecker\Plugin\LinkStatusHandlerBase::handle(): Argument #1 ($link) must be of type Drupal\linkchecker\LinkCheckerLinkInterface, null given, called in /home/kartbook/public_html/kartbook.au/modules/contrib/linkchecker/src/Plugin/QueueWorker/LinkStatusHandle.php on line 79 in Drupal\linkchecker\Plugin\LinkStatusHandlerBase->handle() (line 107 of /modules/contrib/linkchecker/src/Plugin/LinkStatusHandlerBase.php).

#0 <fileloc>/modules/contrib/linkchecker/src/Plugin/QueueWorker/LinkStatusHandle.php(79): Drupal\linkchecker\Plugin\LinkStatusHandlerBase->handle()
#1 <fileloc>/core/lib/Drupal/Core/Cron.php(270): Drupal\linkchecker\Plugin\QueueWorker\LinkStatusHandle->processItem()
#2 <fileloc>/core/lib/Drupal/Core/Cron.php(235): Drupal\Core\Cron->processQueue()
#3 <fileloc>/core/lib/Drupal/Core/Cron.php(162): Drupal\Core\Cron->processQueues()
#4 <fileloc>/core/lib/Drupal/Core/ProxyClass/Cron.php(75): Drupal\Core\Cron->run()
#5 <fileloc>/core/modules/system/src/CronController.php(38): Drupal\Core\ProxyClass\Cron->run()
#6 [internal function]: Drupal\system\CronController->run()
#7 <fileloc>/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(123): call_user_func_array()
#8 <fileloc>/core/lib/Drupal/Core/Render/Renderer.php(638): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#9 <fileloc>/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(121): Drupal\Core\Render\Renderer->executeInRenderContext()
#10 <fileloc>/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(97): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext()
#11 <fileloc>/vendor/symfony/http-kernel/HttpKernel.php(181): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#12 <fileloc>/vendor/symfony/http-kernel/HttpKernel.php(76): Symfony\Component\HttpKernel\HttpKernel->handleRaw()
#13 <fileloc>/core/lib/Drupal/Core/StackMiddleware/Session.php(53): Symfony\Component\HttpKernel\HttpKernel->handle()
#14 <fileloc>/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\Core\StackMiddleware\Session->handle()
#15 <fileloc>/core/lib/Drupal/Core/StackMiddleware/ContentLength.php(28): Drupal\Core\StackMiddleware\KernelPreHandle->handle()
#16 <fileloc>/core/modules/big_pipe/src/StackMiddleware/ContentLength.php(32): Drupal\Core\StackMiddleware\ContentLength->handle()
#17 <fileloc>/core/modules/page_cache/src/StackMiddleware/PageCache.php(201): Drupal\big_pipe\StackMiddleware\ContentLength->handle()
#18 <fileloc>/core/modules/page_cache/src/StackMiddleware/PageCache.php(138): Drupal\page_cache\StackMiddleware\PageCache->fetch()
#19 <fileloc>/core/modules/page_cache/src/StackMiddleware/PageCache.php(87): Drupal\page_cache\StackMiddleware\PageCache->lookup()
#20 <fileloc>/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\page_cache\StackMiddleware\PageCache->handle()
#21 <fileloc>/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle()
#22 <fileloc>/core/lib/Drupal/Core/StackMiddleware/AjaxPageState.php(36): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle()
#23 <fileloc>/core/lib/Drupal/Core/StackMiddleware/StackedHttpKernel.php(51): Drupal\Core\StackMiddleware\AjaxPageState->handle()
#24 <fileloc>/core/lib/Drupal/Core/DrupalKernel.php(741): Drupal\Core\StackMiddleware\StackedHttpKernel->handle()
#25 <fileloc>/index.php(19): Drupal\Core\DrupalKernel->handle()
#26 {main}

@ar_howard , please try the mentioned patch

https://www.drupal.org/files/issues/2025-05-05/3522806-04.patch →

Blame PHP 8.2+ for this in combination with contrib.

Still needs steps to reproduce and tests ✌️