Oops, I mean LGTM2. On Tuesday, September 29, 2026 at 10:26:00 AM UTC-7 Dan Clark wrote:
> Thanks Mason! LGTM1 pending those tests. > > On Tuesday, September 29, 2026 at 7:47:40 AM UTC-7 Mason Freed wrote: > >> On Monday, September 28, 2026 at 11:32:35 AM UTC-7 Dan Clark wrote: >> >> *> 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 >> >> <https://wpt.fyi/results/css/css-anchor-position?label=master&label=experimental&aligned&q=position-visibility>* >> >> The only of these tests I saw covering anchor-valid is this one: >> https://wpt.fyi/results/css/css-anchor-position/position-visibility-anchor-valid.tentative.html >> >> <http://Is%20this%20feature%20fully%20tested%20by%20web-platform-tests?%20Yes%20https://wpt.fyi/results/css/css-anchor-position?label=master&label=experimental&aligned&q=position-visibility> >> . >> >> Maybe not too many tests are needed, but does this fully cover the >> behavior called out in the summary? "[The new version is] better defined >> to be clear that only the default anchor matters , resolving a lot of >> ambiguity"? >> >> >> Sorry, I should have added to that response that my CL to implement the >> feature <https://crrev.com/c/8453827> adds more testing. >> >> >> E.g. the test shows that this is hidden: >> <div id="target2" class="target" style="top: anchor(--does-not-exist >> bottom);">target2</div> >> >> But it'd be nice to include a case where position-anchor is unset but >> anchor() refers to an anchor name that actually does exist: >> <div id="target3" class="target" style="top: anchor(--a1 >> bottom);">target2</div> >> >> >> I believe this is "Case 7" from the >> new position-visibility-anchor-valid-001.html test. >> >> >> And maybe a similar set of checks with anchor-size(). >> >> >> This is indeed missing. I'll land another CL to add test cases for >> anchor-size like this - thanks for the suggestion. >> >> >> Another case that seems important to have is an element that has a valid >> default anchor, but another anchor it depends on doesn't resolve. If I'm >> understanding correctly that would have resulted in the element being >> hidden in the original proposal >> <https://github.com/w3c/csswg-drafts/issues/7758#issuecomment-1965540529>, >> but in the current proposal the element would be shown, since only the >> default anchor matters. >> >> >> Also a good (missing) suggestion. I'll add it! >> >> Thanks, >> Mason >> >> >> Thanks, >> Dan >> >> On Friday, September 25, 2026 at 2:53:52 PM UTC-7 Chris Harrelson wrote: >> >> Thanks! LGTM1 >> >> On Fri, Sep 25, 2026 at 1:24 PM Mason Freed <[email protected]> wrote: >> >> >> 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 desktop157DevTrial on desktop157Shipping on Android157DevTrial >> on Android157Shipping on WebView123 >> >> *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. >> 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%3DNeDgCzuuVhhsikDnHq_iZu2XkXuK1cJ6dT23134Qg4WKV0w%40mail.gmail.com >> >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAM%3DNeDgCzuuVhhsikDnHq_iZu2XkXuK1cJ6dT23134Qg4WKV0w%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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