[csswg-drafts] [web-animations-1] Reject old-style `:before` pseudo-element syntax (#4472)

birtles has just created a new issue for https://github.com/w3c/csswg-drafts:

== [web-animations-1] Reject old-style `:before` pseudo-element syntax ==
Background is the discussion in #4437.

As of that change, `KeyframeEffect` now has a [`pseudoElement`](https://drafts.csswg.org/web-animations-1/#dom-keyframeeffect-pseudoelement) member whose [syntax](https://drafts.csswg.org/selectors/#pseudo-element-syntax) is defined by Selectors Level 4.

That definition requires UAs to accept the old single colon syntax (`:before`) as well as the double colon syntax (`::before`).

I was under the impression we wanted to phase that historical artifact out of the web platform so that new APIs like this should reject `:before` and only accept `::before`.

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/4472 using your GitHub account

Received on Wednesday, 30 October 2019 05:16:04 UTC