- From: L. David Baron <dbaron@dbaron.org>
- Date: Mon, 21 Jan 2013 14:39:23 +0000
- To: whatwg@whatwg.org
I thought I'd brought this issue up before, but I can't seem to find a record of it. http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#attr-style-scoped currently says that, inside scoped style sheets, @page rules are ignored, but other @-rules are honored, scoped either to the style sheet or to the subtree. I think it makes perfect sense to honor @-rules whose effects are scoped to the style sheet (@namespace, also @charset if it weren't already ignored) or @-rules whose effects are to condition the rules inside of them (all the rules in css3-conditional: @media, @supports) or import more rules (@import). But I think it's a large amount of extra implementation complexity to honor @-rules whose purpose is to build global dictionaries (in particular, @keyframes and @font-face), and I suspect the end result of honoring them would yield technology that's more confusing for authors. Anything that can be done by changing the meaning of an @keyframes or @font-face rule within a subtree could also be done by declaring a different animation rule or font-family within that subtree. I suspect the extra clarity from the latter makes it a better authoring practice anyway, so I don't think implementations should be required to add support for a feature that it's better to not use. Thus I think the specification should mandate that @keyframes and @font-face are ignored in scoped style sheets, just like @page. I think it would also be good if the specification left the effects of unknown @-rules undefined until whether they should be supported can be properly considered. -David -- 𝄞 L. David Baron http://dbaron.org/ 𝄂 𝄢 Mozilla http://www.mozilla.org/ 𝄂
Received on Monday, 21 January 2013 14:39:51 UTC