Warning: Undefined array key "current"

Hallöchen,

ich habe ein Backend-Formular, wenn ich dieses speichere oder zurücksetze, dann bekomme ich beim klicken auf einen Link im Backend-Menu die übrige Fehlermeldung.
Verlasse ich das Formular nach dem speichern über "zurück" oben rechts, tritt dieses Phänomen nicht auf.

Ich kapiere nicht was da das problem sein soll.


Contao: 5.0.7
PHP: 8.1

Code:

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ErrorException:
Warning: Undefined array key "current"

  at vendor/contao/core-bundle/src/EventListener/StoreRefererListener.php:81
  at Contao\CoreBundle\EventListener\StoreRefererListener->__invoke(object(ResponseEvent), 'kernel.response', object(TraceableEventDispatcher))
    (vendor/symfony/event-dispatcher/Debug/WrappedListener.php:115)
  at Symfony\Component\EventDispatcher\Debug\WrappedListener->__invoke(object(ResponseEvent), 'kernel.response', object(TraceableEventDispatcher))
    (vendor/symfony/event-dispatcher/EventDispatcher.php:206)
  at Symfony\Component\EventDispatcher\EventDispatcher->callListeners(array(object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener), object(WrappedListener)), 'kernel.response', object(ResponseEvent))
    (vendor/symfony/event-dispatcher/EventDispatcher.php:56)
  at Symfony\Component\EventDispatcher\EventDispatcher->dispatch(object(ResponseEvent), 'kernel.response')
    (vendor/symfony/event-dispatcher/Debug/TraceableEventDispatcher.php:127)
  at Symfony\Component\EventDispatcher\Debug\TraceableEventDispatcher->dispatch(object(ResponseEvent), 'kernel.response')
    (vendor/symfony/http-kernel/HttpKernel.php:196)
  at Symfony\Component\HttpKernel\HttpKernel->filterResponse(object(Response), object(Request), 1)
    (vendor/symfony/http-kernel/HttpKernel.php:184)
  at Symfony\Component\HttpKernel\HttpKernel->handleRaw(object(Request), 1)
    (vendor/symfony/http-kernel/HttpKernel.php:75)
  at Symfony\Component\HttpKernel\HttpKernel->handle(object(Request), 1, true)
    (vendor/symfony/http-kernel/Kernel.php:202)
  at Symfony\Component\HttpKernel\Kernel->handle(object(Request))
    (public/index.php:44)

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