Dangerous code founded by WordFence scanner

I suspect the files that are triggering the alert are in the cache folder. These are actually the files that were downloaded and optimized from your website and cached by the plugin so it doesn’t have to perform the optimization on every request.

The contents are first serialized then encoded with MIME base64 to resolve some issues with saving and retrieving the data on different servers, which would make the codes even more innocuous in my opinion.

If I was using that plugin it would be interesting to hear what about these codes that are triggering this alert. This would be one way to validate that it’s actually doing what it’s supposed to be doing.