LGTM1. Given the positive replies from Firefox and WebKit and the small use counters I believe it's fine doing this change.
Cheers, Rego On 15/09/2021 14:55, Mike Taylor wrote: > Hey Rune, > > Is there any way for developers to know behavior has changed on their > sites when this ships? (Or alternatively, any clues for folks triaging > bugs, besides bisecting?). > > I'm wondering about sites where breakage is pretty bad. Would it be > useful to ship a devtools issue (probably overkill given the use counter > data, especially if they're over-counting problematic cases...)? > > (Also, I asked dholbert if he thinks it's something Gecko would want to > ship in https://bugzilla.mozilla.org/show_bug.cgi?id=1730763#c2) > > > On 9/14/21 6:12 PM, Rune Lillesveen wrote: >> >> >> Contact emails >> >> [email protected] <mailto:[email protected]> >> >> >> Specification >> >> http://drafts.csswg.org/css-contain-1/#c3 >> <http://drafts.csswg.org/css-contain-1/#c3> >> >> >> Summary >> >> Used values for contain different from none on the root or body >> elements will disable propagation of CSS properties from body as per >> specification[1]. [1] https://drafts.csswg.org/css-contain-1/#c3 >> <https://drafts.csswg.org/css-contain-1/#c3> >> >> >> This change was brought to the CSSWG because the unconditionally >> propagating body styles to the viewport would create circular >> dependencies for CSS Container Queries. For instance, a propagated >> writing-mode from body to the viewport, when orthogonal to the outer, >> could change the size of root element which in turn could affect style >> resolution for body via container queries, which again could result in >> a different computed writing-mode for body. See the github issue for >> details: https://github.com/w3c/csswg-drafts/issues/5913 >> <https://github.com/w3c/csswg-drafts/issues/5913>. It should be noted >> that the CSSWG has regretted introducing propagation from body and >> have resolved >> <https://github.com/w3c/csswg-drafts/issues/6079#issuecomment-816307011> >> on not introducing new properties to be propagated from body. >> >> The implementation was added to M93 behind a flag along with use >> counters for used contain values different from none on html root and >> body: >> >> https://chromestatus.com/metrics/feature/timeline/popularity/3936 >> <https://chromestatus.com/metrics/feature/timeline/popularity/3936> >> https://chromestatus.com/metrics/feature/timeline/popularity/3937 >> <https://chromestatus.com/metrics/feature/timeline/popularity/3937> >> >> These use counters cover more cases than potentially problematic ones, >> as they do not detect if the styles are different on body and root and >> would make any differences. Still the use counters are low - 0.0004% >> and 0.0008% respectively. >> >> >> Blink component >> >> Blink>CSS >> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3ECSS> >> >> >> TAG review >> >> None. Change to a W3C Recommendation in the CSSWG. >> >> >> TAG review status >> >> Not applicable >> >> >> Risks >> >> >> Interoperability and Compatibility >> >> * Not shipping this change would block shipping CSS Container >> Queries, or cause stateful style/layout issues. >> * Low use counters for containment on body and root. >> * There is an interop risk if the other engines do not change their >> implementations. The use counters indicate that, at least at the >> moment, applying containment to root and body is rare. >> >> I have not filed a standards position for Gecko. This seems like a >> rather small change compared to APIs typically filed as a >> standards position. I got a quick reply on the webkit-thread. >> Issues are filed for both browsers and I have triaged the failing >> tests on wpt.fyi accordingly. >> >> Gecko: No signals https://bugzilla.mozilla.org/show_bug.cgi?id=1730763 >> <https://bugzilla.mozilla.org/show_bug.cgi?id=1730763> >> >> WebKit: No >> objection: >> https://lists.webkit.org/pipermail/webkit-dev/2021-September/031982.html >> <https://lists.webkit.org/pipermail/webkit-dev/2021-September/031982.html> >> >> Web developers: No signals > > -- > You received this message because you are subscribed to the Google > Groups "blink-dev" group. > To unsubscribe from this group and stop receiving emails from it, send > an email to [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/f2eb218d-29ac-c82b-6620-ccc81b9be5ed%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/f2eb218d-29ac-c82b-6620-ccc81b9be5ed%40chromium.org?utm_medium=email&utm_source=footer>. -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/d4d873fb-6413-76c0-d268-5339e7d38661%40igalia.com.
