Support :is() and :where() CSS pseudo-classes

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SemiKebab
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Support :is() and :where() CSS pseudo-classes

Unread post by SemiKebab » 2022-12-04, 11:44

Title says it all. You may want to support the :is() and :where() CSS pseudo-classes, which are already supported by all major browsers, except the now-defunct IE. I searched on the UXP issues but didn't find a ticket about them.

Note that contrarily to :not(), their parameter is a forgiving selector list.

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Nuck-TH
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Re: Support :is() and :where() CSS pseudo-classes

Unread post by Nuck-TH » 2022-12-04, 12:30

Are there any particular reasons to prioritize this against currently known issues? "Google one day pushed one more shiny and Mozilla blindly followed" is not such reason.

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FranklinDM
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Re: Support :is() and :where() CSS pseudo-classes

Unread post by FranklinDM » 2022-12-04, 12:33

SemiKebab wrote:
2022-12-04, 11:44
You may want to support the :is() ...
On a side note, we do have partial support for this pseudo-class function in the form of :-moz-any, but it will have to be updated to conform to the new spec.

SemiKebab
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Re: Support :is() and :where() CSS pseudo-classes

Unread post by SemiKebab » 2022-12-04, 12:52

Nuck-TH wrote:
2022-12-04, 12:30
Are there any particular reasons to prioritize this against currently known issues? "Google one day pushed one more shiny and Mozilla blindly followed" is not such reason.
Not prioritizing in particular. Though, I think it's a great feature.

SemiKebab
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Re: Support :is() and :where() CSS pseudo-classes

Unread post by SemiKebab » 2023-02-25, 02:12

This feature is making its way into Pale Moon, thanks to the great work of FranklinDM, see #2078 and #2110.

SemiKebab
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Re: Support :is() and :where() CSS pseudo-classes

Unread post by SemiKebab » 2023-03-09, 07:34

For the record, the jQuery 3.6.4 release led me to this note:
To add to that, a recent CSSWG resolution made ":is()" & ":where()" the only pseudos with forgiving parsing; browsers are in the process of making ":has()" parsing unforgiving.

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