JSFiddle - React, Tailwind, and code Playground

HTML

<select name="lang_choice" id="lang_choice">
<option value="en">English</option>
<option value="fr" selected="selected">French</option>
<option value="de">Deutsch</option>
</select>

JavaScript

$('<img class=flagicon src="http://pascha.org/img/'+$("select#lang_choice").val()+'.png">').insertAfter("#lang_choice");
$("select#lang_choice").change(function(){
	$(".flagicon").attr("src", 'http://pascha.org/img/'+$("select#lang_choice").val()+'.png');
	});