Re: [css-conditional][quirks] Quirks mode and @supports/CSS.supports

On Thu, 26 Nov 2015 09:56:55 +0100, Simon Pieters <simonp@opera.com> wrote:

> On Thu, 26 Nov 2015 02:07:44 +0100, Florian Rivoal <florian@rivoal.net>  
> wrote:
>
>>
>>> On 26 Nov 2015, at 03:19, Simon Pieters <simonp@opera.com> wrote:
>>>
>>> What is the interaction between
>>>
>>> https://drafts.csswg.org/css-conditional/#at-supports
>>> https://drafts.csswg.org/css-conditional/#the-css-interface
>>>
>>> ...and...
>>>
>>> https://quirks.spec.whatwg.org/#the-hashless-hex-color-quirk
>>> https://quirks.spec.whatwg.org/#the-unitless-length-quirk
>>>
>>> Testing in  
>>> http://software.hixie.ch/utilities/js/live-dom-viewer/saved/3765 it  
>>> appears that in Blink/WebKit/Gecko apply the quirks in @supports, but  
>>> not in CSS.supports(). Presto doesn't apply the quirks to @supports  
>>> and doesn't have CSS.supports(). I haven't checked IE/Edge. I suggest  
>>> we specify what Blink/WebKit/Gecko do.
>>
>> I did the implementation in Presto, and not applying the quirks was not  
>> intentional. There was no rationale for it, only oversight. I agree  
>> that @supports should match what the browser actually consumes, and if  
>> it supports quirky things, then @supports should reflect that.
>
> We could also say that the quirks don't apply in that context, like they  
> don't apply in calc(). Quirks don't have to make sense, just be  
> Web-compatible enough. But I don't see that supporting the quirks in  
> @supports is a problem, so I don't mind taking the shortest path to  
> interop here.
>
>> Btw, why not do the same in CSS.supports()? Any particular reason  
>> there, or are you just proposing aligning with implementations?
>
> The latter. I don't know if it was deliberate in implementations. I  
> stumbled over this at https://codereview.chromium.org/1475903002

Defined in  
https://github.com/whatwg/quirks/commit/007fb633fb730628f6b1702592aaf546a8d590c4

-- 
Simon Pieters
Opera Software

Received on Wednesday, 16 December 2015 12:35:21 UTC