JSFiddle - React, Tailwind, and code Playground

HTML

<select id="foo" size="5">
    <option>1</option>
    <option>2</option>
    <option>3</option>
    <option>4</option>
    <option>5</option>
    <option selected="true">6</option>
    <option>7</option>
    <option>8</option>
    <option>9</option>
    <option>10</option>
    <option>11</option>
    <option>12</option>
    <option>13</option>
    <option>14</option>
    <option>15</option>
</select>

JavaScript

var sel = document.getElementById("foo");
var optsLen = sel.options.length;
var selIndex = sel.selectedIndex;
var size = sel.size;
if (selIndex>=size) {
    var newIndex = selIndex+size+1;
    if (newIndex>optsLen) {
        newIndex = optsLen;
    }
    sel.selectedIndex = newIndex;
    setTimeout(function(){sel.selectedIndex = selIndex},1);
}