JSFiddle - React, Tailwind, and code Playground
HTML
<div id="selects">
<select name="folder1"></select>
<select name="folder2"></select>
<select name="folder3"></select>
</div>
JavaScript
if (an element exists in the div 'selects' with name="folder3") {
return false;
} else {
$('#selects').append('<select name="folder3"></select>');
}