Background Processes Error after Upgrading

TypeError: IPS\core\extensions\core\EditorLocations\Widget::_rebuildWidgetContent(): Argument #1 ($content) must be of type string, null given, called in /home/*****/dev.thedarkblues.co.uk/applications/core/extensions/core/EditorLocations/Widget.php on line 202 (0)
#0 /home/*****/dev.thedarkblues.co.uk/applications/core/extensions/core/EditorLocations/Widget.php(202): IPS\core\extensions\core\EditorLocations\Widget->_rebuildWidgetContent()
#1 /home/*****/dev.thedarkblues.co.uk/applications/core/extensions/core/EditorLocations/Widget.php(132): IPS\core\extensions\core\EditorLocations\Widget->performRebuild()
#2 /home/*****/dev.thedarkblues.co.uk/applications/core/extensions/core/Queue/RebuildLazyLoadNonContent.php(94): IPS\core\extensions\core\EditorLocations\Widget->rebuildLazyLoad()
#3 /home/*****/dev.thedarkblues.co.uk/system/Task/Task.php(111): IPS\core\extensions\core\Queue\RebuildLazyLoadNonContent->run()
#4 /home/*****/dev.thedarkblues.co.uk/applications/core/modules/admin/system/background.php(103): IPS\Task::runQueue()
#5 /home/*****/dev.thedarkblues.co.uk/system/Helpers/MultipleRedirect/MultipleRedirect.php(104): IPS\core\modules\admin\system\background->IPS\core\modules\admin\system\{closure}()
#6 /home/*****/dev.thedarkblues.co.uk/applications/core/modules/admin/system/background.php(154): IPS\Helpers\MultipleRedirect->__construct()
#7 /home/*****/dev.thedarkblues.co.uk/system/Dispatcher/Controller.php(128): IPS\core\modules\admin\system\background->process()
#8 /home/*****/dev.thedarkblues.co.uk/applications/core/modules/admin/system/background.php(58): IPS\Dispatcher\Controller->execute()
#9 /home/*****/dev.thedarkblues.co.uk/system/Dispatcher/Dispatcher.php(169): IPS\core\modules\admin\system\background->execute()
#10 /home/*****/dev.thedarkblues.co.uk/admin/index.php(15): IPS\Dispatcher->run()
#11 {main}

Did a test update of my forum, but when I manually run the Background Processes, or they are done automatically, the above error is encountered.

This means that the background process is stuck and never performed.