What can cause Chrome to give an net::ERR_FAILED on cached content against a server on localhost?

I run into similar problem. I have copied request as fetch in Network tab in devtools.

Then I have run it in browser dev console. There I could read description of the error about CORS. After setting cors on the api server, it worked.

You have to paste the fetch command into the dev console of the same origin and NOT accidentally e.g. open it from stackoverflow.