private function loadStateIdentifiers(): array
    {
        if ($this->stateIdentifiers === null) {
            $this->stateIdentifiers = $this->repository->sudo(
                static function (Repository $repository): array {
                    $stateIdentifiers = [];

                    $stateGroups = $repository->getObjectStateService()->loadObjectStateGroups();
                    foreach ($stateGroups as $stateGroup) {
                        $stateIdentifiers[$stateGroup->identifier] = [];

                        $states = $repository->getObjectStateService()->loadObjectStates($stateGroup);
                        foreach ($states as $state) {
                            $stateIdentifiers[$stateGroup->identifier][] = $state->identifier;
                        }
                    }

                    return $stateIdentifiers;
                }
            );
        }

        return $this->stateIdentifiers;
    }