role="combobox" aria-autocomplete="list"
        aria-haspopup="listbox" aria-expanded="true"
        aria-controls="popup_listbox" aria-activedescendant="cb-ak" />
    <button id="cbButton" tabindex="-1" aria-label="Open">▼</button>
    </div>
    <ul id="popup_listbox" role="listbox" aria-label="States">
    <li id="cb-al" role="option">Alabama</li>
    <li id="cb-ak" role="option" aria-selected="true">Alaska</li>
    </ul>
</div>
```

Note 1: The guidance for `combobox` changed significantly in [ARIA s