JSFiddle - React, Tailwind, and code Playground

HTML

<button id="demo">Click here</button><br/><br/><br/>
<input type="file" id="upload" />

JavaScript

$(function () {
    $('#demo').click(function () {         
        $.ajax({
            type: "POST",
            url: "/echo/json/",
            data: "jsonText",
            dataType: "json",
            //async: false
            }).done(function (msg) {
                $("#upload").click();
            }).fail(function(jqXHR, textStatus, errorThrown){
                alert(textStatus);  
            }); 
         //$("#upload").click();
    });
});