[csswg-drafts] [css-ui-4] Fallout of change from resulting from https://github.com/w3c/csswg-drafts/issues/11494 (#13451)

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

== [css-ui-4] Fallout of change from resulting from https://github.com/w3c/csswg-drafts/issues/11494 ==
In https://github.com/w3c/csswg-drafts/issues/11494#issuecomment-2675800489, it was decided that:

> Summary of the resolution as I understand it:
> 
> 1. `column-rule-*`, `border-*`, and `outline-*` are all under consideration
> 2. Computed value for `*-width` should be independent of `*-style`, i.e. remove the none/hidden special behavior from this stage
> 3. Resolved value (i.e. getComputedStyle) for `border-width` should continue to return 0 if `border-style` is none/hidden, for compat reasons
> 4. If also needed for compat, apply 3 to `outline-width` and `column-rule-width` as well

I implemented this in WebKit very recently, and we have so far received one regression report: https://bugs.webkit.org/show_bug.cgi?id=306818.

In the report, the authors code was assuming that the computed style of `outline-width` would be `0` when `outline-style` was `none`. 

I'm not clear on exactly what criteria we should apply for considering instituting step 4 for `outline-width` (e.g. giving `outline-width` a resolved value of `0` when `outline-style` is `none`), this is one data point in favor of it.

cc [kbabbitt](https://github.com/kbabbitt) [@emilio](https://github.com/emilio) [@fantasai](https://github.com/fantasai) [@tabatkins](https://github.com/tabatkins)

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/13451 using your GitHub account


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Received on Wednesday, 4 February 2026 17:19:51 UTC