Contact emailsmas...@chromium.org Explainer https://developers.google.com/web/updates/2019/02/constructable-stylesheets
Specification https://www.w3.org/TR/cssom-1/#extensions-to-the-document-or-shadow-root-interface Summary The prior specification for adoptedStyleSheets used a FrozenArray backing array. The spec was recently changed, so that the backing array is an ObservableArray. This makes the API easier to use and understand, since it is a true mutable JS array object. For example, normal array operations such as adoptedStyleSheets.push(sheet) can be used. Blink componentBlink <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink> Search tagsadoptedStyleSheets <https://chromestatus.com/features#tags:adoptedStyleSheets>, ObservableArray <https://chromestatus.com/features#tags:ObservableArray> TAG review TAG review statusNot applicable Risks Interoperability and Compatibility Chromium is the only shipped implementation of adoptedStyleSheets. Gecko would like to ship this feature, but has been waiting for the resolution of this issue (FrozenArray vs. ObservableArray) to ship their implementation. This should unblock Gecko [1]. The Edge team supports this change [2]. WebKit continues to be skeptical [3] of this usefulness of this feature, despite the general agreement of the rest of the web components community [4], and the support of the developer community [5][6][7]. So the interop risk is mainly that WebKit decides not to implement this feature. Compat risks (from the change from FrozenArray to ObservableArray) should be minimal, as the same re-assignment semantics will continue to work. As documentation improves, and usage expands, we expect re-assignment usage to wane, and mutation (e.g. adoptedStyleSheets.push()) to expand. [1] https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-834749590 [2] https://github.com/whatwg/webidl/issues/1027#issuecomment-940204556 [3] https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-826036758 [4] https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-825055766 [5] https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-577941622 [6] https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-827229881 [7] https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-827234689 Gecko: Positive ( https://github.com/whatwg/webidl/issues/1027#issuecomment-940204556) WebKit: Negative ( https://github.com/WICG/construct-stylesheets/issues/45#issuecomment-826036758 ) Web developers: Strongly positive Several large web component developers are strongly positive on this feature and change. See several links in the "Interoperability and Compatibility Risks" section. Other signals: Debuggability This feature should remain debuggable via existing JS/devtools infrastructure. There is good support for adoptedStyleSheets already in devtools. Is this feature fully tested by web-platform-tests <https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md> ?Yes Flag nameBecause few compat risks are anticipated, and because it is relatively difficult to switch the representation (FrozenArray to ObservableArray) via a feature flag, this feature will be enabled by default. This will be done at the start of a new Chromium milestone (M99), and bugs will be monitored carefully in case any breakages are observed. Requires code in //chrome?False Tracking bughttps://crbug.com/1236777 Estimated milestones No milestones specified Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5638996492288000 This intent message was generated by Chrome Platform Status <https://www.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/CAM%3DNeDijQpNhJJJUjtCzLSDrPngTHYY31H4oJrULxm%3DtxLVHew%40mail.gmail.com.
