Re: [csswg-drafts] [css-conditional-5] Add ability to test for at-rule preludes (#6966)

Looking to restart discussion on this feature. I read the minutes from the previous discussion and understand the concern about things that parse in a forgiving manner. I spent some type prototyping in Blink today, and I think @lilles [suggestion](https://github.com/w3c/csswg-drafts/issues/6966#issuecomment-1353157253) to have unknown parts fail `@supports at-rule()` would be feasible for MQs at least.

I wasn't sure about [this comment](https://github.com/w3c/csswg-drafts/issues/6966#issuecomment-1412982096) from @mirisuzanne though:

> It looks like where we left off after TPAC, we still need to re-form the basic proposal - and then we can include this update to the proposal.

It sounds like there might have been other concerns that came up, but if there were I didn't pick up on them in my read of the minutes. Does someone who was in the previous discussions recall what they were?

(@andruud captured a few interesting cases in https://github.com/w3c/csswg-drafts/issues/11116, https://github.com/w3c/csswg-drafts/issues/11117, https://github.com/w3c/csswg-drafts/issues/11118, but they don't strike me as things that would call for re-forming the basic proposal.)

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Received on Thursday, 3 July 2025 01:35:23 UTC