[V6˖] Unsupported characters in key identifiers - PHPSocialNetwork/phpfastcache GitHub Wiki
As of the V6, the following characters can not longer being a part of the key identifier: {}()/\@:
If you try to do so, an \phpFastCache\Exceptions\phpFastCacheInvalidArgumentException
will be raised.
You must replace them with a safe delimiter such as .|-_
More information on psr-6 definitions.