JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="moo1"/>
<input type="text" id="moo"/>

JavaScript

function simulateClick(id) {
    var evt = document.createEvent("MouseEvents");
    evt.initMouseEvent("click", true, true, window, 1, 0, 0, 0, 0,
        false, false, false, false, 0, null);

    var cb = document.getElementById(id);
    cb.dispatchEvent(evt);
}

$('#moo').click(function() { this.value+='a'});

simulateClick('moo')