From 10ce8d9a3b93463c969795e732abf96fdb3133a8 Mon Sep 17 00:00:00 2001 From: Hashim Khan Date: Thu, 23 Jul 2026 07:34:45 +0500 Subject: [PATCH] docs: list browser versions that already have native fetch Clarify when whatwg-fetch is unnecessary by documenting minimum versions with native window.fetch support. Refs #1483. --- README.md | 32 +++++++++++++++++++++++++++----- 1 file changed, 27 insertions(+), 5 deletions(-) diff --git a/README.md b/README.md index c2882839..ac9f1f07 100644 --- a/README.md +++ b/README.md @@ -328,16 +328,38 @@ controller.abort() ## Browser Support +This polyfill is intended for older browsers that lack a native `window.fetch` +implementation: + - Chrome - Firefox - Safari 6.1+ - Internet Explorer 10+ -Note: modern browsers such as Chrome, Firefox, Microsoft Edge, and Safari contain native -implementations of `window.fetch`, therefore the code from this polyfill doesn't -have any effect on those browsers. If you believe you've encountered an error -with how `window.fetch` is implemented in any of these browsers, you should file -an issue with that browser vendor instead of this project. +**Do not use this polyfill if you only target modern browsers.** All currently +maintained browsers ship a native, standards-compliant `fetch`. Including +`whatwg-fetch` in those environments is unnecessary and adds extra bundle size. + +Browsers where this polyfill is **not needed** (native `fetch` is available): + +| Browser | Minimum version with native `fetch` | +| ------- | ----------------------------------- | +| Chrome | 42+ | +| Firefox | 39+ | +| Edge (Chromium) | All versions | +| Edge (Legacy) | 14+ | +| Safari (macOS) | 10.1+ | +| Safari (iOS) | 10.3+ | +| Opera | 29+ | +| Samsung Internet | 4.0+ | + +If your supported browser list only includes the versions above (or newer), do +not install or import this polyfill. + +Note: in browsers that already provide native `window.fetch`, code from this +polyfill does not take effect. If you believe you've encountered an error with +how `window.fetch` is implemented in any of those browsers, you should file an +issue with that browser vendor instead of this project. [fetch specification]: https://fetch.spec.whatwg.org