Does it make sense to add an Implicit Value for Role?

Maybe something like:

Implicit Value for Role: Default for aria-controls is undefined.

See the paragraph beginning with:

However, required states and properties that are absent are an author error.

in the State and Property Attribute Processing section, which ends with:

The characteristics table associated with each WAI-ARIA role has an " Implicit Value for Role " entry that specifies the value of a state or property to use in the context of that role when the state or property is missing.

Yeah - we nee

Approving as-is, but would like an answer on whether or not adding Implicit value for role makes sense (or would just add more confusion).
Thanks @jnurthen !

We have to do something - either add an implicit value or move to supported... Lets add to today's agenda and see what others think.

+1 for the new state of this PR, which does 2 things:

• Adds "When the popup is displayed," so that the requirement for authors says the following:

  When the popup is displayed, authors MUST set aria-controls on a combobox element to a value that refers to the combobox popup element.

• Moves aria-controls from required to supported in the characteristics table.