Comment 26 for bug 1187993

The WAI-ARIA Authoring Pattern for a combobox might help us think through exactly what behavior would be most helpful: https://www.w3.org/TR/wai-aria-practices-1.1/#combobox

For what it's worth, their "combobox with grid popup" example seems pretty similar to the current autosuggest implementation: https://www.w3.org/TR/wai-aria-practices-1.1/examples/combobox/aria1.1pattern/grid-combo.html#ex_label

Also adding the needsdiscussion tag, because it seems like we should get some consensus on the user experience we want for this autosuggest.