[csswg-drafts] [css-values] Spec does not reject duplicate `<request-url-modifier>`s, but WPT does (#12151)

AtkinsSJ has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-values] Spec does not reject duplicate `<request-url-modifier>`s, but WPT does ==
[This test](https://wpt.live/css/css-values/urls/url-request-modifiers-invalid.sub.html) requires that a `url()` with more than one of the same `<request-url-modifier>` be treated as invalid, but I can't find anything in the spec that says this is invalid. The 3 major engines all pass these tests, so evidently that's the desired behaviour, but it'd be good to specify it.

The [`<url>`](https://drafts.csswg.org/css-values-4/#url-value) and [`<url-modifier>`](https://drafts.csswg.org/css-values-4/#url-modifiers) definitions in CSS Values 4 do not place any requirements on repeated modifiers.

Likewise, the definitions in CSS Values 5 of [`<request-url-modifier>`s](https://drafts.csswg.org/css-values-5/#request-url-modifiers) do not say anything about more than one of a given type appearing in a `url()`.

cc: @weinig as you wrote that particular test.

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/12151 using your GitHub account


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Received on Friday, 2 May 2025 15:47:03 UTC