Actually I take that back - I'll add my LGTM once the Adoption gate is filled out in the Chromestatus entry.
On Wed, Oct 28, 2026 at 5:23 AM Chris Harrelson <[email protected]> wrote: > LGTM2 > > On Tue, Oct 27, 2026 at 7:08 PM Alex Russell <[email protected]> > wrote: > >> LGTM1; thanks for the note about interop risk, makes this easier to >> approve. >> >> On Monday, October 26, 2026 at 2:56:32 PM UTC-7 Chromestatus wrote: >> >>> *Contact emails* >>> [email protected] >>> >>> *Specification* >>> https://drafts.csswg.org/css-values-4/#linked-properties >>> >>> *Summary* >>> Makes the computed value of the background-* longhands keep the number >>> of comma-separated values the author specified, instead of repeating or >>> truncating it to the background-image layer count. Repeating and truncating >>> are used-value behavior: "The computed values of the coordinating list >>> properties are not affected by such truncation or repetition." This feature >>> would implement the behavior defined in the >>> https://drafts.csswg.org/css-values-4/ Appendix A. >>> >>> *Blink component* >>> Blink>CSS >>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ECSS%22> >>> >>> *Web Feature ID* >>> background <https://webstatus.dev/features/background> >>> >>> *Motivation* >>> The behavior defined in the "Appendix A: Coordinating List-Valued >>> Properties" of the CSS Values And Units L4 specification has been discussed >>> recently and agreed that it should stand. This makes Chrome the only >>> browser diverging in the specified behavior. >>> >>> *Initial public proposal* >>> *No information provided* >>> >>> *TAG review* >>> *No information provided* >>> >>> *TAG review status* >>> Not applicable >>> >>> *Goals for experimentation* >>> None >>> >>> *Risks* >>> >>> >>> *Interoperability and Compatibility* >>> The new behavior this feature provides is implemented already by Firefox >>> and Safari, so it's Chrome catching up in this case; hence, the interop >>> risk is zero. Regarding compatibility, making the background-* properties >>> align "coordinated list group" is what matches the current specified >>> behavior, which the CSSWG agreed on keep. Some engines implemented weird >>> truncation rules, that's why there were some WPT not following the spec. >>> The resolution [1] was to update the tests and observe whether any compat >>> issue appears in the next months. [1] >>> https://github.com/w3c/csswg-drafts/issues/12791#issuecomment-4040285092 >>> >>> *Gecko*: Shipped/Shipping Firefox was the only one implementing the >>> behavior defined in the spec. >>> https://github.com/w3c/csswg-drafts/issues/12791#issuecomment-4040285092 >>> >>> *WebKit*: Shipped/Shipping ( >>> https://developer.apple.com/documentation/safari-technology-preview-release-notes/stp-release-246) >>> See >>> the bug https://bugs.webkit.org/show_bug.cgi?id=315771 for details >>> >>> *Web developers*: No signals >>> >>> *Other signals*: >>> >>> *WebView application risks* >>> >>> Does this intent deprecate or change behavior of existing APIs, such >>> that it has potentially high risk for Android WebView-based applications? >>> *No information provided* >>> >>> >>> *Debuggability* >>> *No information provided* >>> >>> *Will this feature be supported on all six Blink platforms (Windows, >>> Mac, Linux, ChromeOS, Android, and Android WebView)?* >>> Yes >>> >>> *Is this feature fully tested by web-platform-tests >>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?* >>> Yes >>> * >>> https://wpt.fyi/results/css/css-backgrounds/parsing?label=experimental&label=master&aligned >>> * >>> https://wpt.fyi/results/css/css-backgrounds/animations/background-position-interpolation.html?label=experimental&label=master&aligned >>> * >>> https://wpt.fyi/results/css/css-backgrounds/animations/background-size-interpolation.html?label=experimental&label=master&aligned >>> * >>> https://wpt.fyi/results/css/css-masking/parsing?label=experimental&label=master&aligned >>> >>> *Flag name on about://flags* >>> *No information provided* >>> >>> *Finch feature name* >>> *No information provided* >>> >>> *Non-finch justification* >>> *No information provided* >>> >>> *Rollout plan* >>> Will ship enabled for all users >>> >>> *Requires code in //chrome?* >>> False >>> >>> *Tracking bug* >>> https://issues.chromium.org/issues/40855581 >>> >>> *Estimated milestones* >>> Shipping on desktop 159 >>> Shipping on Android 159 >>> Shipping on WebView 159 >>> Shipping on iOS 159 >>> >>> *Anticipated spec changes* >>> >>> Open questions about a feature may be a source of future web compat or >>> interop issues. Please list open issues (e.g. links to known github issues >>> in the project for the feature specification) whose resolution may >>> introduce web compat/interop risk (e.g., changing to naming or structure of >>> the API in a non-backward-compatible way). >>> *No information provided* >>> >>> *Link to entry on the Chrome Platform Status* >>> https://chromestatus.com/feature/5144333908049920?gate=6114123363516416 >>> >>> *Links to previous Intent discussions* >>> Intent to Prototype: >>> https://groups.google.com/a/chromium.org/g/blink-dev/c/eny3Exk0b8w/m/HiXscXadAgAJ >>> >>> >>> This intent message was generated by Chrome Platform Status >>> <https://chromestatus.com>. >>> >> -- >> 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 visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/1a9a7278-d5a2-42a7-8556-2086d23e5fa9n%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/1a9a7278-d5a2-42a7-8556-2086d23e5fa9n%40chromium.org?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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