1854104 - Consider CSS attr() fallback

Status: NEW

(DevTools :: Inspector: Rules, enhancement, P3)

Description

[Oliver Medhurst [:canadahonk]]

Support for CSS attr()'s fallback (eg attr(foo, "fallback")) is being implemented and shipped in Bug 1448248. It should display okay in DevTools currently but it could possibly be improved (needs investigation). No other browsers implement or ship it at this time.

Spec: https://drafts.csswg.org/css-values-5/#attr-notation

Comment 1

[Nicolas Chevobbe [:nchevobbe]]

We could do what is done for var() and display the value not being used in a "disabled"-grey color
CanadaHonk, can we detect that in javascript that the fallback is used?

Comment 2

[Oliver Medhurst [:canadahonk]]

No unfortunately, the spec doesn't add anything to DOM/etc exposing any fallback info afaik. I would be happy to add it but would likely need an upstream spec issue deciding how best to do so.

Comment 3

[Emilio Cobos Álvarez [:emilio]]

Well, we can detect it using element.hasAttribute(...) right?