On Wednesday, May 27, 2026 at 5:24:51 PM UTC+2 Rick Byers wrote:
Thanks for proposing <https://github.com/web-platform-dx/web-features/issues/3864> a new feature ID to track support for this feature, but it looks like the report was missing some information and so got closed. Ensuring we have a good summary description and tracking of features is really important to enable web developers and AI coding agents to reason about the availability of the feature (eg. see webstatus.dev and the baseline project <https://web.dev/baseline>). Please add the requested information to the feature ID request and reopen it (or file a new one). Rick On Wed, May 27, 2026 at 11:18 AM Vladimir Levin <[email protected]> wrote: LGTM1 Thanks On Wednesday, May 27, 2026 at 11:09:51 AM UTC-4 Alex Russell wrote: This seems extremely cool; is there perhaps an Explainer somewhere? This note on the Mozilla standards position request has most of that content and might help folks get more comfortable with the proposal as a stand-alone document; https://github.com/mozilla/standards-positions/issues/ 1396#issuecomment-4363280736 Best, Alex On Tuesday, May 26, 2026 at 8:38:49 PM UTC-7 Chromestatus wrote: *Contact emails* [email protected] *Specification* https://drafts.csswg.org/css-color-5/#relative-alpha *Summary* Relative alpha colors refer to an origin color, and only change the alpha channel. The meaning of alpha channels is defined in CSS Color 4 § 4.2 Representing Transparency in Colors: the <alpha-value> syntax. *Blink component* Blink>CSS <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ECSS%22> *Web Feature ID* Missing feature *Motivation* Relative alpha colors provide a direct CSS way to derive a translucent version of an existing color without rewriting its color channels. Authors currently need to duplicate component values or create separate precomputed tokens when they want “the same color, different opacity.” The CSS Color 5 alpha() function preserves the original color components and only changes alpha, which reduces authoring overhead and makes color tokens easier to reuse and maintain. *Initial public proposal* *No information provided* *TAG review* *No information provided* *TAG review status* Not applicable *Goals for experimentation* None *Risks* *Interoperability and Compatibility* *No information provided* *Gecko*: No signal (https://github.com/mozilla/standards-positions/ issues/1396) *WebKit*: No signal (https://github.com/WebKit/standards-positions/ issues/657) *Web developers*: No signals https://nerdy.dev/relative-alpha seems like a signal. *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 *Flag name on about://flags* *No information provided* *Finch feature name* CSSAlphaColorFunction *Rollout plan* Will ship enabled for all users *Requires code in //chrome?* False *Tracking bug* https://issues.chromium.org/issues/492246715 *Estimated milestones* Shipping on desktop150 Shipping on Android150 Shipping on WebView150 *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/5070160203481088?gate=6508530389614592 *Links to previous Intent discussions* Intent to Prototype: https://groups.google.com/a/chromium.org/d/msgid/blink- dev/69b4e4d0.050a0220.b9121.0139.GAE%40google.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/4b6dd5d4-4411-4d41-af2b- 008420db8d61n%40chromium.org <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/4b6dd5d4-4411-4d41-af2b-008420db8d61n%40chromium.org?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/7a6a6f9d-36da-4090-bf7b-dcb6c81a6330n%40chromium.org.
