[csswg-drafts] [css-content-3] Animation of 'content' (#8623)

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

== [css-content-3] Animation of 'content' ==
Currently the Animation Type of the `content` property is “discrete”. However, because the `none` value can cause the box to disappear when applied to a pseudo-element, this has similar problems to `display: none` in keyframes, see discussion in https://github.com/w3c/csswg-drafts/issues/6429

The solution we chose for `display: none` was to replace it with `display: revert-layer` in keyframes. But that doesn't quite work for `content` for two reasons:
* `content: none` on regular elements does not delete the box, only its contents, so it's not necessary to limit it
* `content: normal` on certain pseudo-elements computes to `none`, so it needs to be limited also.

Possible options I can think of, none of which seem amazing...
* Both `none` and `normal` are excluded from keyframes, and are converted to `revert-layer`.
* A computed value of `none` in an animation or transition frame (i.e. that originated in either the Animations or Transitions cascade origins) is converted to `""`.
* A computed value of `none` in a keyframe is converted to `""` only on the `::before`/`::after` pseudo-elements.
* We make `content` Not Animatable.
* Something else?


Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/8623 using your GitHub account


-- 
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config

Received on Monday, 20 March 2023 20:43:49 UTC