Matthew: This is really interesting. Could be pretty helpful. People use <canvas> to render a whole webapp. Instead of using HTML elements, they draw pixels, so it's not accessible, but they want exact control over appearance. Can put fallback elements inside the canvas. They don't get rendered, but they're available to AT. This allows you to put those elements on the canvas in a particular place. They say it's great because it'll be good for accessibility. That aspect does sound good. Concerned that use cases aren't explained well enough, because if you're using canvas to avoid native elements, why would you use this?

Jeffrey: We should ask them to explain the use cases, if they're not clear enough in the explainer. I'm pretty sure they'd have a partner who's interested in using this, but they might not have enough partners.

Matthew: It's sometimes not enough to show a particular element for example if the focus indicator actually lives on one of its ancestors. They said you could use this for a menu in a game. But if you're placing things at particular pixel locations, you're doing a lot of the layout yourself, and what if the user has changed the base font size? They talked about "and its children", so maybe you wouldn't place menu items. That should be made very clear to developers.

Jeffrey: Can we point them to a particular accessibility group?

Matthew: Point them to APA. We might point them toward the ARIA people. We have the TAG question about use cases, in addition to the accessibility question. I'll post a comment this evening.

we discuss and agree Matthew's comment

Tess: I think this has been tried before.... in ancient whatwg mailing list issues...

Matthew posted a comment, including a couple of edits suggested by Jeffrey