[css-view-transitions-2] view-transition-name: auto when matching id should namespace

[vmpstr]

We have a view-transition-name: auto that can use the id attribute from the element as the view transition name. (https://www.w3.org/TR/css-view-transitions-2/#auto-vt-name)

I think it can be confusing if, for example, in the old state we match id=foo and on the other side that pairs with css view-transition-name: foo.

The proposal is to "namespace" id matching. Basically id=foo would only match with id=foo and not with view-transition-name: foo. Or, in other words, names generated by the id attribute can only match elements that have names that are also generated by the id attribute.

@nt1m @noamr fyi

[nt1m]

I think this makes sense

[noamr]

I'm personally happy to resolve on this, perhaps asynchronously since WG meeting time is hard to get.

/cc @jakearchibald
I think this is less footgunny than the previous auto and is perhaps satisfactory.

[jakearchibald]

I still think this is a bad feature with a bad name. But it was force-shipped.