Re: [csswg-drafts] [css-view-transitions-2] Specify view-transition-nane: match-element (#12968)

I dug in a bit more and I figured out: there is [a section on auto naming with `auto`/`match-element`](https://drafts.csswg.org/css-view-transitions-2/#auto-vt-name) in the spec, but the problem is that [the definition of the `view-transition-name` prop](https://drafts.csswg.org/css-view-transitions-2/#view-transition-name-prop) does not mention these keywords are possible values.

> ```bs
>  <pre class=propdef>
>  Name: view-transition-name
>  Value: none | <<custom-ident>>
>  Initial: none
>  Inherited: no
>  Percentages: n/a
>  Computed Value: as specified
>  Animation type: discrete
>  </pre>
> ```

So my first suggestion would be to extend list of values for `view-transition-name` as follows:

```diff
-  Value: none | <<custom-ident>>
+  Value: none | match-element | auto | <<custom-ident>>
```

Both terms could then use a (simple) description but one without an example, as the description can link to [the section on auto naming](https://drafts.csswg.org/css-view-transitions-2/#auto-vt-name) for examples.

I’d also recommend to use “element identity” in the descriptions, as that’s the terminology we’ve used in the discussions and one that make it clear.

In https://developer.chrome.com/blog/view-transitions-in-2025#auto-name_elements_with_view-transition-name_match-element I also included the following note, which could make a good note in the spec as well:

> Note: Elements in different documents have a different identity, therefore match-element can only be used in same-document view transitions.



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Received on Monday, 20 October 2025 09:49:40 UTC