Today I discovered a strange problem; my Cordova application, which uses the new Fetch API was working fine on iOS, but was failing on Android (with Crosswalk).

It turns out that the error was coming from the Fetch API which was saying URL scheme must be "http" or "https" for CORS request.. Manually setting the mode to no-cors with fetch(path, { mode: 'no-cors' }) gives the error URL scheme "cdvfile" is not supported..

So it seems that the native Fetch API in Chrome doesn’t like the cdvfile schema, but the polyfill loads it happily.

Therefore as an ugly but workable hack, simply throw away the native implementation before loading the polyfill to ensure that Android also uses the polyfilled version!

window.fetch = null;

require("whatwg-fetch");