JSFiddle - React, Tailwind, and code Playground

HTML

<select id="selecttest">
<option value="1">one</option>
<option value="2">two</option>
<option value="3">free</option>
<option value="4">four</option>
<option value="5">five</option>
<option value="6">six</option>
<option value="7">seven</option>
<option value="8">height</option>
<option value="9">nine</option>
<option value="10">ten</option>
<option value="11">eleven</option>
<option value="12">twelve</option>
<option value="13">thirdteen</option>
</select>

<input type="button" value="testing" id="MyButton"/>

JavaScript

$('#MyButton').on("click",function(){

$("#selecttest").attr("size", 8);
$("#selecttest").css("position","fixed");
$('#MyButton').css("margin-left", $("#selecttest").width() + 5);
});

$('#selecttest').on("change",function(){

$("#selecttest").attr("size", 1);

});