Contact emailskhushalsa...@chromium.org, vmp...@chromium.org Explainer https://github.com/WICG/shared-element-transitions/blob/main/overflow-on-replaced-elements.md https://github.com/w3c/csswg-drafts/issues/7058
Specificationhttps://drafts.csswg.org/css-overflow/#overflow-properties Summary This change allows developers to use the existing `overflow` property with replaced elements that paint outside the content-box. Paired with `object-view-box` this can be used to create an image with a custom glow or shadow applied, with proper ink-overflow behavior like a CSS shadow would have. Blink componentBlink>CSS <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3ECSS> TAG reviewhttps://github.com/w3ctag/design-reviews/issues/750 TAG review statusPending Risks Interoperability and Compatibility This feature changes the behaviour of the existing overflow property on replaced elements (img, video, canvas). Currently `overflow:visible` in a developer stylesheet on such elements is ignored during paint and the content is clipped to the element's content-box. With this feature, `overflow:visible` will result in content outside the element's content-box to paint as ink overflow. We've collected use counter data to measure the number of sites which could be affected by this. The use counter data collected over 1 week of a stable release (M102) is as follows. We collected 2 different counters explained below. * The first measures any instance where overflow is explicitly set from developer styles to visible. The percentage of page loads with this is 2.16%. * The second measures the above instances but only includes the cases with object-fit set to cover or none or object-position set to any value other than the default (50% 50%). The rationale behind this counter is to exclude cases which can not cause overflow (such as object-fit:contain), even if overflow is set to visible. The percentage of page loads with this is 0.017%. *Gecko*: No signal ( https://github.com/mozilla/standards-positions/issues/659) *WebKit*: No signal ( https://lists.webkit.org/pipermail/webkit-dev/2022-June/032317.html) *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? Debuggability This is a CSS property which can be debugged in the devtools style panel similar to other CSS properties. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, 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 Flag nameCSSOverflowForReplacedElements *Note: Because of the compat risk with this feature, this flag can be controlled via Finch. This will allow us to rollback with a server-side config change if needed.* Requires code in //chrome?False Tracking bughttps://bugs.chromium.org/p/chromium/issues/detail?id=1321217 Estimated milestones M105 Anticipated spec changes N/A Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5137515594383360 Links to previous Intent discussionsIntent to prototype: https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAMLuWUykJWEAqVzcUy15fpBNdA68508Mny_1z--FCBKXRTZOFQ%40mail.gmail.com <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/camluwuykjweaqvzcuy15fpbnda68508mny_1z--fcbkxrtz...@mail.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 blink-dev+unsubscr...@chromium.org. To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAMLuWUze8JV6twLfhPBwkXj_UBMGApU048OdY33hYQn_KDj2rA%40mail.gmail.com.
