JSFiddle - React, Tailwind, and code Playground

HTML

<div id="div1">
<p>
This is div1. My event was added via jQuery and is listened for by vanilla JS.
</p>
<p>
  Enter the number 2 to have the event fired.
</p>
<input type="text" id="input1" />
<button id="button1">
Submit
</button>
</div>
<div id="div2">
  <p>
    This is div2. My event was added via vanilla JS and is listened for by jQuery.
  </p>
  <p>
    Enter the number 2 to have the event fired.
  </p>
  <input type="text" id="input2" />
  <button id="button2">
  Submit
  </button>
</div>

JavaScript

var $input1 = $("#input1");
var $input2 = $("#input2");
var input1 = document.getElementById("input1");
var input2 = document.getElementById("input2");

var event1 = "civicscienceEvent1";
var event2 = "civicscienceEvent2";

$("#button1").click(function() {
	if (+$input1.val() == 2) {
    $input1.trigger(event1, {message: "Event 1 triggered!"});
  }
});

input1.addEventListener(event1, function(e) {
    console.log("Event 1 triggered! message=" + e.detail.message);
});

$("#button2").click(function() {
	if (+$input2.val() == 2) {
    var event = new CustomEvent(event2, {detail: {message: "Event 2 triggered!"}});
    input2.dispatchEvent(event);
  }
});

$input2.on(event2, function(e) {
    console.log("Event 2 fired, but I don't know how to get the message!");
});