crbug.com/107113

by int32_t

HTML

<select id=s1 multiple>
    <option>c1</option>
    <option>c2</option>
</select>
<input type="button" value="Toggle"  id=b1>
<pre id=console></pre>

JavaScript

function f1() {
    var s1 = document.getElementById('s1');
    s1.disabled = !s1.disabled;
}

function showIndex() {
    var s1 = document.getElementById('s1');
    var c = document.getElementById('console');
    c.innerHTML = 'selectedIndex: ' + s1.selectedIndex;
}

document.getElementById('b1').addEventListener('click', f1, false);
setInterval(showIndex, 100);