public function getAll()
    {
        $result = $this->getListOptionValue();

        foreach ($result as $key => $item) {
            // remove non-array items (unexpected state, though can happen when upgrading from an old Piwik)
            if (is_array($item)) {
                $this->logger->info("Found array item in DistributedList option value '{name}': {data}", array(
                    'name' => $this->optionName,
                    'data' => var_export($result, true)
                ));

                unset($result[$key]);
            }
        }

        return $result;
    }