LGTM2 On Tue, Oct 28, 2025 at 10:44 AM Philip Jägenstedt <[email protected]> wrote:
> LGTM1 > > There is some discussion in > https://github.com/mozilla/standards-positions/issues/1302 about whether > this feature triggers more layouts, which it does not IIUC. But if there is > more feedback from Mozilla on this and some changes are needed for Gecko to > avoid extra layout work, we should adjust the spec and implementation as > needed. > > On Thu, Oct 23, 2025 at 8:16 AM Morten Stenshorne <[email protected]> > wrote: > >> *Contact emails* >> [email protected] >> >> *Explainer* >> *No information provided* >> >> *Specification* >> https://drafts.csswg.org/css-anchor-position-1/#anchor-position-size >> >> *Summary* >> When an anchor-positioned element is tethered against an anchor that has >> a transform (or is contained by something with a transform), resolve >> anchor() and anchor-size() functions against the bounding box of the >> transformed anchor. >> >> *Blink component* >> Blink>Layout >> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ELayout%22> >> >> *Web Feature ID* >> anchor-positioning <https://webstatus.dev/features/anchor-positioning> >> >> *Motivation* >> https://drafts.csswg.org/css-anchor-position-1/#anchor-position-size says >> that transform effects on an anchor should affect the anchor box, so that >> anchor-positioned elements may be positioned with regards to where an >> anchor is on screen. This chimes well with how scroll offsets are also >> taken into account. >> https://drafts.csswg.org/css-anchor-position-1/#scroll This behavior is >> crucial for creating sophisticated UI effects where elements need to remain >> logically connected while one of them is being transformed. Consider a >> tooltip that points to a button. If the button rotates or scales on hover, >> you want the tooltip to move along with it, maintaining its relative >> position. >> >> *Initial public proposal* >> *No information provided* >> >> *TAG review* >> *No information provided* >> >> *TAG review status* >> Pending >> >> *Risks* >> >> >> *Interoperability and Compatibility* >> *No information provided* >> >> *Gecko*: No signal ( >> https://github.com/mozilla/standards-positions/issues/1302) >> >> *WebKit*: No signal ( >> https://github.com/WebKit/standards-positions/issues/558) >> >> *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 >> >> *Flag name on about://flags* >> *No information provided* >> >> *Finch feature name* >> CSSAnchorWithTransforms >> >> *Rollout plan* >> Will ship enabled for all users >> >> *Requires code in //chrome?* >> False >> >> *Tracking bug* >> https://issues.chromium.org/issues/382294252 >> >> *Estimated milestones* >> Shipping on desktop 144 >> Shipping on Android 144 >> Shipping on WebView 144 >> >> *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/5201048700583936?gate=5152239350054912 >> >> *Links to previous Intent discussions* >> Intent to Prototype: >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAKWZFm6cenwaNiH0YEpJae2n%3DfWz7O553%3D9fKSukBL_KhvUK0A%40mail.gmail.com >> >> >> 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/CAKWZFm7qjp6xQ2TX2jSFaXszEZnyBSKA-DSddU4B2P4mKLU4GQ%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAKWZFm7qjp6xQ2TX2jSFaXszEZnyBSKA-DSddU4B2P4mKLU4GQ%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/CAARdPYdb6iroDcWtbBDUNPoTF8aPQ24%3D8tex2_L%3DUPJVMDBhLg%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAARdPYdb6iroDcWtbBDUNPoTF8aPQ24%3D8tex2_L%3DUPJVMDBhLg%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/CAOMQ%2Bw_GDLR2%2B9CK0VAw6AOEN_EtDDB5PYyzFjQE1MMZP8y%2BeA%40mail.gmail.com.
