1017875 - (picture-prefon) Pref on the picture element by default

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect, P5)

Description

[John Schoenick [:johns]]

Picture (Bug 870022) and img srcset (Bug 870022) will both be pref'd off on initial landing, this tracks remaining issues blocking pref'ing them on by default.

Comment 1

[Richard Newman [:rnewman]]

Very relevant to mobile, so tracking-fennec? and marking for relnote for when this ships.

(Hoping I got the keyword right...)

Comment 2

[Andrew McCreight [:mccr8]]

I believe the tracking flag "relnote-firefox" is the proper thing, not the relnote keyword.

Comment 3

[Sylvestre Ledru [:Sylvestre]]

Indeed. We are discussing about removing this keyword to clear the confusion.


Release Note Request (optional, but appreciated)
[Why is this notable]: Cool new features and the Opera + Chrome have it
[Suggested wording]: I think they deserve two dedicated items:
"HTML5: picture element implemented"
"HTML5: srcset attribute on img"
[Links (documentation, blog post, etc)]: Probably their documentation

Comment 4

[James Willcox (:snorp) ([e-mail]) (he/him)]

Can we turn this on for Nightly right now?

Comment 5

[John Schoenick [:johns]]

Part of Bug 1037643 is blocking the tests from landing, which we really should not turn anything on without. The other blockers are minor and have patches, but I've been pulled away from this the past few weeks for some high priority e10s stuff. I should be able to get back to this next week and get things landed so we can flip this on early in the cycle

Comment 6

[Henri Sivonen (:hsivonen)]

We shouldn't pref this on before ensuring that the <img src> preloader doesn't preload the wrong stuff. <picture> and srcset are all about loading the right image variant, so also loading the wrong variant is particularly bad considering the goals of the feature. (Bug 1067345.)

Comment 7

[Brad Lassey [:blassey] (use needinfo?)]

filter on [mass-p5]

Comment 8

[John Schoenick [:johns]]

Attachment: Pref on <picture> element and update test

Comment 9

[Josh Matthews [:jdm]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=69b64df23a25

Comment 10

[Josh Matthews [:jdm]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=a1686082ab80

Comment 11

[Josh Matthews [:jdm]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/de043394a41d
https://hg.mozilla.org/integration/mozilla-inbound/rev/2bb299df4c33

Comment 12

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/de043394a41d
https://hg.mozilla.org/mozilla-central/rev/2bb299df4c33

Comment 13

[Florian Bender]

Just requested relnote? from Bug 1018389, saw comment 3 afterwards. FTR, "my" relnote? request:

Release Note Request (optional, but appreciated)
[Why is this notable]: responsive images – also see Bug 1018389
[Suggested wording]: Implemented srcset attribute and <picture> element for responsive images
[Links (documentation, blog post, etc)]:

Since this and Bug 1018389 are closely connected, a singular entry in the Release Notes should suffice.

Comment 14

[Lukas Blakk [:lsblakk] use ?needinfo]

Have added to the Aurora 38 notes as: 

Implemented srcset attribute and <picture> element for responsive images