Caching fails to download assets in Chrome 85

[jampy]

As stated here, Chrome now dislikes lots of parallel fetch() invocations unless the response body is consumed.

This practically prevents the initial download of the offline-plugin cache and also consequent updates. The Service Worker fails to install.

It's stuck in this status and fails after 10 minutes or so:

It took me a whole day to track down the problem to this code: https://github.com/NekR/offline-plugin/blob/master/src/misc/sw-template.js#L605

I don't want to say that the code is wrong but due to the behavior of Chrome the Promise.all() must be changed so that fetch() and cache.put() are done together.

I'm out of time to help you with a pull request on the master branch but here is my patched version for the 4.9.1 version: https://gist.github.com/jampy/4330e2008b09450da72a25aba2aa90be#file-sw-template-js-L629

[jampy]

FYI, my patch needed a little fix. Here is the better version: https://gist.github.com/jampy/635ab91e60907a7fe38fb18a1c11a94d#file-sw-template-js-L631