Add CSS Nesting

[Schweinepriester]

Spec: https://drafts.csswg.org/css-nesting-1/

https://cssdb.org/#nesting-rules

https://twitter.com/Fyrd/status/1103820945758674944 B-)

Chrome bug: https://bugs.chromium.org/p/chromium/issues/detail?id=1095675

Firefox bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1648037

Safari bug: https://bugs.webkit.org/show_bug.cgi?id=223497

[edouard-lopez]

I was looking for info about this and can't find any on CanIUse despite the fact the proposal being [merged ~2 years ago](The w3c/csswg-drafts#2878).

The process on adding information is foreign to me, but should this be added under other or unoff status?

[Pomax]

As update to this, https://www.w3.org/TR/css-nesting-1 is now a public working draft.

[Fyrd]

Now available at https://caniuse.com/css-nesting

[BenjaminAster]

CSS Nesting is now available in Chromium 109.0.5368.0 with the experimental web platform features flag enabled.

[Schweinepriester]

@BenjaminAster PR is ready #6500

[BenjaminAster]

@Schweinepriester Oh, didn't see that, thanks!