Vsch\TranslationManager\Manager::usageCachePrefix PHP Method

    public function usageCachePrefix()
    {
        if ($this->usageCacheTransKey == null) {
            $this->cachePrefix();
            $this->usageCacheTransKey = $this->persistentPrefix ? $this->persistentPrefix . 'usage_info' : '';
        }
        return $this->persistentPrefix;
    }