Obtain cache files chrome extension

Is there a way to obtain/read cache files using a chrome extension without NPAPI but javascript?

I have tried searching with NP开发者_StackOverflowAPI but I am unable to find a good tutorial on it or how can it be done using NPAPI.

Javascript is restricted from accessing the filesystem in all cases that I am aware of, though I admit that I don't know much about Chrome extensions.

The only way I know of to access arbitrary files would be with an NPAPI plugin as part of the extension. If you decide to go this route, I suggest you look at FireBreath, which is an abstraction that simplifies and solves most of the issues people run into with NPAPI plugins.