src/Observing/Observer.php
public function removeEventDispatcher(EventDispatcherBridgeInterface $dispatcher): ObserverInterface
    {
        $dispatcherHash = \spl_object_hash($dispatcher);
        if (isset($this->dispatchersList[$dispatcherHash])) {
            //Dispatcher not found, do nothing "silently"
            unset($this->dispatchersList[$dispatcherHash]);
        }

        return $this;
    }
public function removeEventDispatcher(EventDispatcherBridgeInterface $dispatcher): ObserverInterface
    {
        $dispatcherHash = \spl_object_hash($dispatcher);
        if (isset($this->dispatchersList[$dispatcherHash])) {
            //Dispatcher not found, do nothing "silently"
            unset($this->dispatchersList[$dispatcherHash]);
        }

        return $this;
    }
{@inheritdoc}