[csswg-drafts] [animation-triggers-1] formalize the <event-trigger-event> value (#14129)

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

== [animation-triggers-1] formalize the <event-trigger-event> value ==
Currently the spec for values allowed as [`<event-trigger-event>`](https://drafts.csswg.org/animation-triggers-1/#typedef-event-trigger-event) is practically placeholder:

> [`<event-trigger-event>`](https://drafts.csswg.org/animation-triggers-1/#typedef-event-trigger-event) = activate | interest | click | touch | dblclick | keypress(`<string>`) |  ...

We should formalize the values for this type.

## Options to consider:

1. Start with all events? Or start with a limited list and expand as we go?
2. Some events could benefit from a functional form with modifier args, as already implied in the spec, such as `key` for keyboard , and `button` for mouse/pointer, etc. Should we allow functional? Allow both functional and keyword? Only functional?
3. If we do allow functional form, which args for each event?
4. It's already suggested to add `activate` and `interest` (which IMO is great), but do we need `activatein`/`activateout`/`interestin`/`interestout`? Or do we leave these to be automatically decided based on usage, i.e. `event-trigger: --t interest / interest` automatically becomes `interestin / interestout`. Or perhaps `interest(in|out)`?

## Proposal

1. Start with a limited list and expand. Probably after there's a first prototype deployed in the wild. I think starting with keyboard/mouse/pointer/`interest`/`activate` as suggested is a good start.
2. I think both are good (if it's not a problem).
3. I guess starting with the suggested `key` for keyboard events is fine as a starting point. Probably as a space delimited list? And if so, probably needs a special case for `" "` to be handled as `Space`.
4. I think starting with just `interest` and `activate` with "in/out" being decided automatically based on usage should be a good start.

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cc @flackr @DavMila 

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/14129 using your GitHub account


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Received on Friday, 3 July 2026 14:18:33 UTC