JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery.mask/1.14.15/jquery.mask.min.js"></script>
<input type="text" id="comp_nota" name="comp_nota" />

JavaScript

$("#comp_nota").focus(function(){
	$(this).val($(this).val().replace('/',''));
	$(this).mask("999999");
}).blur(function(){
	$(this).mask("99/9999");
});