</p>

<p>

Authors MUST ensure the popup element associated with a <code>combobox</code> has a role of <rref>listbox</rref>, <rref>tree</rref>, <rref>grid</rref>, or <rref>dialog</rref>.

Authors MUST set <pref>aria-controls</pref> on a <code>combobox</code> element to a value that refers to the <code>combobox</code> popup element.

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

</p>

<p>

Elements with the role <code>combobox</code> have an implicit <pref>aria-haspopup</pref> value of <code>listbox</code>.

<tr>

<th class="role-required-properties-head">Required States and Properties:</th>

<td class="role-required-properties">

<ul>

<li><pref>aria-controls</pref></li>

<li><sref>aria-expanded</sref></li>

</ul>

<sref>aria-expanded</sref>

</td>

</tr>

<tr>

<ul>

<li><pref>aria-activedescendant</pref></li>

<li><pref>aria-autocomplete</pref></li>

<li><pref>aria-controls</pref></li>

<li><pref>aria-errormessage</pref></li>

<li><pref>aria-haspopup</pref></li>

<li><sref>aria-invalid</sref></li>