On Fri, Sep 25, 2026 at 9:36 AM Chris Harrelson <[email protected]> wrote:
> My thought is that, because Firefox doesn't ship anchor-valid yet, it > seems helpful to just file the positions request to encourage interop on > this subfeature. Especially since this feature came a bit later than the > others due to additional spec discussion to align on its semantics, so > perhaps it fell through the cracks a bit (like it did in Chromium until > just now). > Fair point. Done: https://github.com/mozilla/standards-positions/issues/1457 Thanks, Mason > On Fri, Sep 25, 2026 at 9:30 AM Mason Freed <[email protected]> wrote: > >> >> On Thu, Sep 24, 2026 at 5:07 PM Chris Harrelson <[email protected]> >> wrote: >> >>> Could you file a Mozilla standards request? >>> >> >> So there's already a (positive) standards position for anchor positioning >> as a whole: https://github.com/mozilla/standards-positions/issues/794. >> Do you think `anchor-valid` by itself deserves its own standards position? >> I think perhaps we should think about #794 as a position on the entire >> feature, including all sub-features. If you disagree, of course I'm happy >> to file a new one. >> >> Thanks, >> Mason >> >> >> >>> On Wed, Sep 23, 2026 at 3:56 PM Mason Freed <[email protected]> wrote: >>> >>>> *Contact emails* >>>> [email protected] >>>> >>>> *Explainer* >>>> *No information provided* >>>> >>>> *Specification* >>>> https://drafts.csswg.org/css-anchor-position-1/#position-visibility >>>> >>>> *Summary* >>>> The `anchors-valid` value was implemented as part of >>>> https://crbug.com/329703412 but subsequently reverted, due to spec >>>> questions about the exact definition of the value. Since that time, the >>>> value has been renamed to `anchor-valid` (see >>>> https://chromestatus.com/feature/5136123851571200) and also better >>>> defined to be clear that only the default anchor matters, resolving a lot >>>> of ambiguity, and making this value shippable. >>>> >>>> *Blink component* >>>> Blink>CSS >>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ECSS%22> >>>> >>>> *Web Feature ID* >>>> anchor-positioning <https://webstatus.dev/features/anchor-positioning> >>>> >>>> *Motivation* >>>> *No information provided* >>>> >>>> *Initial public proposal* >>>> *No information provided* >>>> >>>> *Search tags* >>>> position-visibility >>>> <https://chromestatus.com/features#tags:position-visibility>, >>>> anchor-valid <https://chromestatus.com/features#tags:anchor-valid>, >>>> anchors-valid <https://chromestatus.com/features#tags:anchors-valid> >>>> >>>> *TAG review* >>>> *No information provided* >>>> >>>> *TAG review status* >>>> Not applicable >>>> >>>> *Goals for experimentation* >>>> None >>>> >>>> *Risks* >>>> >>>> >>>> *Interoperability and Compatibility* >>>> This is new support for a value for `position-visibility` so it should >>>> not create compat risks. Shipping this value will improve interop - WebKit >>>> already ships it. >>>> >>>> *Gecko*: No signal >>>> >>>> *WebKit*: Shipped/Shipping >>>> >>>> *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-anchor-position?label=master&label=experimental&aligned&q=position-visibility >>>> >>>> *Flag name on about://flags* >>>> *No information provided* >>>> >>>> *Finch feature name* >>>> CSSPositionVisibilityAnchorValid >>>> >>>> *Rollout plan* >>>> Will ship enabled for all users >>>> >>>> *Requires code in //chrome?* >>>> False >>>> >>>> *Tracking bug* >>>> https://crbug.com/333421963 >>>> >>>> *Estimated milestones* >>>> Shipping on desktop 157 >>>> DevTrial on desktop 157 >>>> Shipping on Android 157 >>>> DevTrial on Android 157 >>>> Shipping on WebView 123 >>>> >>>> *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/5136856479039488?gate=5692419038380032 >>>> >>>> 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/CAM%3DNeDgQ_W7-2FxYgaXc4-r7-vuaq1rexfHn4w4YEEW-Cz0%2BSA%40mail.gmail.com >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAM%3DNeDgQ_W7-2FxYgaXc4-r7-vuaq1rexfHn4w4YEEW-Cz0%2BSA%40mail.gmail.com?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 visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAM%3DNeDjXTYLG_kz2nEhK19VGFOvQQZcds38-6jzoDk7ZeNBUQg%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAM%3DNeDjXTYLG_kz2nEhK19VGFOvQQZcds38-6jzoDk7ZeNBUQg%40mail.gmail.com?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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