Safari 11.1 shouldn't polyfill `fetch`

[Morozzzko]

What

Safari 11.1 shouldn't receive polyfill for fetch because it already has it

Details

We can see that https://caniuse.com/?search=fetch says that Safari supports fetch since 10.1

I've checked it on Browserstack (Mac OS Monterey, Safari 11.1), and it indeed loads a polyfill:

even though the browser has it anyway

[romainmenke]

The fetch polyfill also includes patches for Request, Response and Headers. Some of these are required up to Safari 12.1

https://github.com/mdn/browser-compat-data/issues/2006#issuecomment-457277312

[ffxsam]

This might be related, but I noticed IntersectionObserver being polyfilled in Safari on iOS 15, when it already exists. So there might be some feature detection issues in Safari in general.

[romainmenke]

@ffxsam That is because of this issue and is unrelated to fetch : https://github.com/Financial-Times/polyfill-library/issues/1192