LGTM3 On 9/29/26 10:26 a.m., 'Dan Clark' via blink-dev wrote:
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/329703412but 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 <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 becauseyou 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]. 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