When i was checking the review of a content i got this error message once i press backward button
Warning: Undefined array key "undefinedasync" in Drupal\diff\Controller\PluginRevisionController->buildLayoutNavigation() (line 205 of modules/contrib/diff/src/Controller/PluginRevisionController.php).
Drupal\diff\Controller\PluginRevisionController->buildLayoutNavigation(Object, '8325', '8329', 'undefinedasync') (Line: 161)
Drupal\diff\Controller\PluginRevisionController->compareEntityRevisions(Object, Object, Object, 'undefinedasync') (Line: 49)
Drupal\diff\Controller\NodeRevisionController->compareNodeRevisions(Object, Object, Object, 'undefinedasync')
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 580)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 169)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 81)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 718)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)
Go to any existing content 'node' and compare two revisions then pressing backward you should
see the error