Keyboard behavior for the interesttarget attribute

[mfreed7]

What is the issue with the HTML Standard?

Some references first:

• The interest invokers explainer's keyboard section
• The OpenUI discussion thread about keyboard behavior
• A section of the explainer that discusses the alternative idea of using delayed-focus as the trigger.

This issue is a narrowed down version of the OpenUI discussion above, to hone in on the right final behavior. Essentially, the explainer lays this out:

For keyboard users, the UA will provide a hot-key such as Alt-Down, which will “show interest” in the element. Another hot-key such as the ESC key will provide a way to trigger “loseinterest”. These hot-keys must be chosen by the UA to be convenient for the user, while also not conflicting with existing UA-provided and OS-provided hot-keys. Other ideas include Alt-Space or Ctrl-Space for the show interest hot key.

Additionally, the appearance of the focus ring will be altered slightly when focus is on elements with interesttarget. This allows the user to discover that something is “different” about this element, and know that the keyboard activation hot-key will allow them to show interest. Since accessibility guidelines state that color alone cannot be enough to differentiate states, this focus ring change will likely need to be something like a slightly-thicker outline, or other shape change.

That's the current direction, coming out of OpenUI discussions. However, this issue is to check that with the folks in WHATWG. In particular:

• Should a hot-key (like Alt-Down) trigger interest, or should merely focusing the element and waiting for the interest-trigger-show-delay time to elapse be enough? Or something else?
• To indicate to the user that an element has interesttarget, should the focus ring be changed (and if so, how), or should something else be done such as changing the browser link preview text at the bottom left/right? Or something else?

[mfreed7]

We had a great discussion of the keyboard behavior today at OpenUI, and I'll be incorporating the conclusions into the explainer shortly. FYI. Thoughts appreciated, here or on the OpenUI issue.