Bug 1854077 Comment 18 Edit History

Note: The actual edited comment in the bug view page will always show the original commenter’s name and original timestamp.

Release Note Request (optional, but appreciated)

[Why is this notable]: New attributes on img/script/link, RequestInit and Link HTTP headers, affecting timing of resource loading.

[Affects Firefox for Android]: Yes.

[Suggested wording]: The `fetchpriority` attribute enables web developers to optimize resource loading by specifying the relative priority of resources to be fetched by the browser. It accepts three values: `auto` (default priority), ̀ low` (lower priority), `high` (higher priority). It can be specified on `script`, `link`, `img` elements, on the `RequestInit` parameter of the `fetch()` method and `Link` response headers. The HTML specification leaves the detailed interpretation of this attribute up to implementers. Firefox will typically use it to increase or decrease the urgency parameter of HTTP/2 and HTTP/3 requests.

[Links (documentation, blog post, etc)]:

https://web.dev/articles/fetch-priority
https://notes.igalia.com/s/dGX-j1_7O#
https://frederic-wang.fr/2024/09/05/my-recent-contributions-to-gecko-fetch-priority/
https://firefox-source-docs.mozilla.org/networking/http/prioritization.html (bug 1915852)
https://html.spec.whatwg.org/#fetch-priority-attribute
https://html.spec.whatwg.org/#the-img-element:fetch-priority-attribute
https://html.spec.whatwg.org/#the-script-element:fetch-priority-attribute
https://html.spec.whatwg.org/#the-link-element:fetch-priority-attribute
https://fetch.spec.whatwg.org/#enumdef-requestpriority
https://html.spec.whatwg.org/#processing-link-headers:fetch-priority-attribute
https://www.rfc-editor.org/rfc/rfc9218.html#section-4.1
Release Note Request (optional, but appreciated)

[Why is this notable]: New attributes on img/script/link, RequestInit and Link HTTP headers, affecting timing of resource loading.

[Affects Firefox for Android]: Yes.

[Suggested wording]: The `fetchpriority` attribute enables web developers to optimize resource loading by specifying the relative priority of resources to be fetched by the browser. It accepts three values: `auto` (default priority),  `low` (lower priority), `high` (higher priority). It can be specified on `script`, `link`, `img` elements, on the `RequestInit` parameter of the `fetch()` method and `Link` response headers. The HTML specification leaves the detailed interpretation of this attribute up to implementers. Firefox will typically use it to increase or decrease the urgency parameter of HTTP/2 and HTTP/3 requests.

[Links (documentation, blog post, etc)]:

https://web.dev/articles/fetch-priority
https://notes.igalia.com/s/dGX-j1_7O#
https://frederic-wang.fr/2024/09/05/my-recent-contributions-to-gecko-fetch-priority/
https://firefox-source-docs.mozilla.org/networking/http/prioritization.html (bug 1915852)
https://html.spec.whatwg.org/#fetch-priority-attribute
https://html.spec.whatwg.org/#the-img-element:fetch-priority-attribute
https://html.spec.whatwg.org/#the-script-element:fetch-priority-attribute
https://html.spec.whatwg.org/#the-link-element:fetch-priority-attribute
https://fetch.spec.whatwg.org/#enumdef-requestpriority
https://html.spec.whatwg.org/#processing-link-headers:fetch-priority-attribute
https://www.rfc-editor.org/rfc/rfc9218.html#section-4.1

Back to Bug 1854077 Comment 18