Neos\Neos\Controller\Module\Management\WorkspacesController::prepareOwnerOptions PHP Method

    protected function prepareOwnerOptions()
    {
        $ownerOptions = ['' => '-'];
        foreach ($this->userService->getUsers() as $user) {
            /** @var User $user */
            $ownerOptions[$this->persistenceManager->getIdentifierByObject($user)] = $user->getLabel();
        }
        return $ownerOptions;
    }