1820058 - Enable CSS content-visibility on Nightly

Status: RESOLVED FIXED

(Core :: Layout, task)

Description

[Daniel Holbert [:dholbert]]

Our content-visibility implementation is relatively complete; let's enable it on Nightly.

(This will get it some broader testing, and it'll help us see what pieces we're still missing as far as bug 1820051 / interop-2023-contain is concerned.)

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: Bug 1820058: Enable about:config pref for CSS 'content-visibility' on Nightly. r?emilio

Comment 2

[Daniel Holbert [:dholbert]]

Try run, in case we have some tests that exercise this feature but don't explicitly enable the pref:
https://treeherder.mozilla.org/jobs?repo=try&revision=c542fd22007353349b330a0ad61a7bc745376e34

Comment 3

[Daniel Holbert [:dholbert]]

I'm glad I checked the Try run. :) It looks like we do have some test-related cleanup to do.

We've got a test failure for exposing ContentVisibilityAutoStateChangeEvent as a property on window (which I think is expected/intentional -- at least, window.ContentVisibilityAutoStateChangeEvent is indeed defined in Chrome -- so we probably just need to update the test expectations):
https://treeherder.mozilla.org/logviewer?job_id=407655619&repo=try&lineNumber=7902

...and a related failure about that same event being unrecognized by a test: dom/events/test/test_all_synthetic_events.html | Unknown event found: ContentVisibilityAutoStateChangeEvent:
https://treeherder.mozilla.org/logviewer?job_id=407655385&repo=try&lineNumber=2560

(I'm guessing both of those^ just require us to update an allow-list with the new event name.)

We also have some failures in layout/style/test:
https://treeherder.mozilla.org/logviewer?job_id=407655492&repo=try&lineNumber=6881
(I think these are pointing at the fact that we have invisible as a value in property_database.js, but in fact the name of the keyword is hidden:
https://searchfox.org/mozilla-central/rev/ed1ebe7bc313eaaec1ed9c2a761fa0fc53e85210/layout/style/test/property_database.js#12972
https://searchfox.org/mozilla-central/rev/ed1ebe7bc313eaaec1ed9c2a761fa0fc53e85210/servo/components/style/values/specified/box.rs#1441-1451
)

And also a WPT failure in one WPT, and an unexpected-pass in another (both of which use content-visibility but are outside of the content-visibility test directory, so they weren't getting the pref enabled):
Unexpected fail: css/css-overflow/overflow-clip-margin-007.html
https://treeherder.mozilla.org/logviewer?job_id=407655358&repo=try&lineNumber=23474
Unexpected pass: html/editing/the-hidden-attribute/hidden-ua-stylesheet.html
https://treeherder.mozilla.org/logviewer?job_id=407655419&repo=try&lineNumber=14252

(That unexpected pass is also accompanied by an earlier WARNING: YOU ARE LEAKING THE WORLD (at least one JSRuntime and everything alive inside it, that is) AT JS_ShutDown TIME. FIX THIS!. That also sounds bad, though I don't know for sure if it's associated with this pref enabling vs. background noise in the log that only got surfaced by the fact that we had other failures there, vs. a random coincidence with an unrelated leak cropping up in the same task.)

Comment 4

[Daniel Holbert [:dholbert]]

Test fixes should be addressed in bug 1821379. I'll land the pref default-value flip after the soft code freeze, to avoid potentially causing Nightly-specific instability while we're trying to stabilize for beta.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e222dc796ab4
Enable about:config pref for CSS 'content-visibility' on Nightly. r=emilio

Comment 6

[Norisz Fay [:noriszfay]]

Backed out for causing failures on test_css-properties-db.js, test_interfaces.html

Backout link

Push with failures - xpcshell
Push with failures - mochitest

Failure log - xpcshell
Failure log - mochitest

Comment 7

[Norisz Fay [:noriszfay]]

Backout merged to central: https://hg.mozilla.org/mozilla-central/rev/db6cd4b2ab0b

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1262759dcc6f
Enable about:config pref for CSS 'content-visibility' on Nightly. r=emilio,devtools-reviewers

Comment 9

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/1262759dcc6f

Comment 10

[Ryan VanderMeulen [:RyanVM]]

Do you want to call this out in the Fx113 Nightly relnotes?

Comment 11

[Daniel Holbert [:dholbert]]

Not at this point; this is just a Nightly-specific pref flip, which I don't think is relevant for release notes.

Comment 12

[Dipika]

MDN doc updates for this feature can be tracked via this issue on Github: https://github.com/mdn/content/issues/26155