JSFiddle - React, Tailwind, and code Playground

HTML

<input class="form-control" type="text" maxlength="10" placeholder="dd/mm/aaaa" onkeyup="formatar('##/##/####', this, event)" name="Tinsem3" id="Cinsem">

JavaScript

function formatar(mascara, documento, e) {
    var code = e.keyCode || e.code;
    if (code == 8 || code == 46) return;
    var i = documento.value.length;
    var saida = mascara.substring(0, 1);
    var texto = mascara.substring(i);
    if (texto.substring(0, 1) != saida) {
        documento.value += texto.substring(0, 1);
    }
}