The early-hints-preconnect showed overall positive results and we would like to enable Early Hints preconnect in the next version. An experiment on Early Hint preload will follow.

https://hg.mozilla.org/mozilla-central/rev/708444bd1b73

Manuel, does it need a mention in our 120 release notes? Thanks

Yes, mentioning in release notes should be worth it. Cloudflare published some blog articles showing big performance improvements in best case scenarios for Early Hints: https://blog.cloudflare.com/early-hints/ https://blog.cloudflare.com/early-hints-performance/

(In reply to Manuel Bucher [:manuel] from comment #5)

Yes, mentioning in release notes should be worth it. Cloudflare published some blog articles showing big performance improvements in best case scenarios for Early Hints: https://blog.cloudflare.com/early-hints/ https://blog.cloudflare.com/early-hints-performance/

Could you request addition in Bugzilla please? There is documentation on how to do it here: https://wiki.mozilla.org/Release_Management/Release_Notes_Nomination

Thanks!

Release Note Request (optional, but appreciated)
[Why is this notable]: Improves performance on servers using this feature. Early Hints might be seen as the spiritual successor of HTTP/2 PUSH (https://developer.chrome.com/blog/removing-push/#alternatives-to-http2-server-push, although this patch is only about enabling Early Hints Preconnect, not yet Early Hints Preload)
[Affects Firefox for Android]: yes
[Suggested wording]:
[Links (documentation, blog post, etc)]:

• https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/103
• https://httpwg.org/specs/rfc8297.html

3rd party blog posts:

• https://blog.cloudflare.com/early-hints/ - "How Cloudflare Can Improve Website Load Times by 30%" 2021-09-16
• https://blog.cloudflare.com/early-hints-performance/ - "Early Hints update: How Cloudflare, Google, and Shopify are working together to build a faster Internet for everyone" 2022-06-23
• https://developer.chrome.com/blog/early-hints/ - "Faster page loads using server think-time with Early Hints" 2022-06-23

Added to Fx120 nightly release notes, https://www.mozilla.org/en-US/firefox/120.0a1/releasenotes/

FF120 MDN docs work for this can be tracked in https://github.com/mdn/content/issues/29779

Just to be clear, I believe that what this does is enable the pref that supports the 103 response with rel/preconnect. So if the server thinks you'll need some resources from example.com, it might send a response like this:

HTTP/1.1 103 Early Hints
Link: <https://example.com>; rel=preconnect;

However the rel=preload version won't work on release until network.early-hints.enabled is enabled by default - right?

Yes, your assessment is correct. rel=preload in Early Hints remains disabled by default for FF120. Only rel=preconnect gets enabled for now. https://github.com/mdn/browser-compat-data/pull/21083/commits/de13a925cf154c2d09bc86b640e348746b74c0ab updates the browser-compat-data.

Thank you. Docs updated appropriately.