Upgrade core-js to version 3

[jbruni]

What?

Reasons to upgrade to core-js version 3 are many, mainly the improved Babel integration.

In our case, we had a theme failing on Internet Explorer 11, and it boiled down to the fact that core-js version 2 does not provide polyfill for NodeList.forEach method. Version 3 of core-js provides this polyfill.

If only Cornerstone was using core-js version 3 out of the box, we would not have ran into that issue.

Tickets / Documentation

• Advantages of core-js version 3

Screenshots (if appropriate)

⬇️ Comparison from core-js's README for v2 and v3:

• https://github.com/zloirock/core-js/tree/v2#iterable-dom-collections
• https://github.com/zloirock/core-js/tree/v3#iterable-dom-collections

---

⬇️ Although NodeList usage is properly detected, core-js version 2 is missing polyfills for IE 11.

[bookernath]

Looks good. Thanks for your contribution and very detailed justification!

Note: we won't cut a release of Cornerstone over the holiday selling season (Black Friday), so this release will be cut in December.

[oggede]

Looks good. Thanks for your contribution and very detailed justification!

Note: we won't cut a release of Cornerstone over the holiday selling season (Black Friday), so this release will be cut in December.

Can you please merge this update ASAP. I've been waiting over 1 month for it to update, as the error causes people to not be able to order on my website. The holiday season is over. Should be able to merge this. Thanks.

[bookernath]

Hi @oggede ,

As this change is already merged to master, you can take advantage of it immediately by simply using the latest code in your custom theme.

However, our release for 4.3.1 containing this change was cut last week, and should be available as an update to the base Cornerstone theme in your control panel this week.

Hope this helps!

[bookernath]

This update is now available for all stores.