[csswg-drafts] [css-values-3] Serialisation of empty url() undefined (#6447)

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

== [css-values-3] Serialisation of empty url() undefined ==
https://drafts.csswg.org/css-values-3/#url-empty, with tests at https://github.com/web-platform-tests/wpt/blob/master/css/css-values/urls/empty.html

This section states:

> If the value of the url() is the empty string (like url("") or url()), the url must resolve to an invalid resource (similar to what the url about:invalid does).

This doesn't appear to define what the computed value of an empty url() is, thus it would appear to be undefined. The tests (by @Emilio) assert that the value _is_ `about:invalid`, rather than it merely being similar to it (resolving to an abstract invalid resource).

Compare with, under Relative URLs above:

> When a <url> appears in the computed value of a property, it is resolved to an absolute URL, as described in the preceding paragraph. The computed value of a URL that the UA cannot resolve to an absolute URL is the specified value.

Current implementation status is:

 * Blink has not implemented https://github.com/w3c/csswg-drafts/commit/e0518924c87638861e6b89cc303667b9421cf152 (which changed the empty URL behaviour)
 * Gecko has, and uses `about:invalid`
 * WebKit has not implemented the change

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/6447 using your GitHub account


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Received on Tuesday, 13 July 2021 20:41:07 UTC