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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