Re: [csswg-drafts] [css-view-transitions-1] Should view transition names be tree scoped? (#10145)

> 1. We should try to solve this problem for CSS naming generally. It's come up for `@font-face` and other features before and I don't think we have a general solution. Designing solutions for each feature independently seems quite bad. I hope @tabatkins and @fantasai can help out here.

[Agreed](https://github.com/w3c/csswg-drafts/issues/10145#issuecomment-2174045257). I had already given Tab an internal ping about this :)

> 2. Exposing names by default very much goes against encapsulation and is not acceptable. Exposing names always needs to be opt-in.

Agreed. The default should be that all names are contained.

> 3. Opting into exposing names globally also seems fraught. That would violate the encapsulation of the encompassing shadow tree. It re-exposing names exposed to it seems reasonable, but that would only go one level up again.

With `contain: names` _(or maybe better `contain-names: …` to not overwrite existing `contain` declarations on those elements)_ you would be able to tweak this on a per-component basis, so it would only bubble up from one shadow boundary to the other.

I think the needs are to:

- Contain all names (default)
- Contain no names
- Contain only a selected set of names

With this authors can also easily opt-in to allowing names to bubble up to the root (i.e. global) in just one go by having a rule that reads `:host { /* <declaration-here-that-indicates-to-contain-no-names> */ }` – this for situations where they are in full control of all custom elements they use.

This `contain-names` property should be limited to apply to only shadow hosts, because I don’t think we’d want authors to sprinkle this around on just any arbitrary element in the tree.

-- 
GitHub Notification of comment by bramus
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/10145#issuecomment-2175638968 using your GitHub account


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

Received on Tuesday, 18 June 2024 09:29:19 UTC