Is there any way of passing additional data via custom events?

Solution 1:

Yes, you can use a MessageEvent or a CustomEvent.

Example usage:

//Listen for the event
window.addEventListener("MyEventType", function(evt) {
    alert(evt.detail);
}, false);

//Dispatch an event
var evt = new CustomEvent("MyEventType", {detail: "Any Object Here"});
window.dispatchEvent(evt);

Solution 2:

pass object with more details as attributes:

var event = new CustomEvent('build', { detail: { 'detail1': "something", detail2: "something else" }});

function eventHandler(e) {
  log('detail1: ' + e.detail.detail1);
  log('detail2: ' + e.detail.detail2);
}

https://developer.mozilla.org/en-US/docs/Web/Guide/Events/Creating_and_triggering_events

Solution 3:

new CustomEvent is not supported in IE https://caniuse.com/#search=CustomEvent

Here is a version which also works on IE9+:

//Listen for the event
window.addEventListener("MyEventType", function(evt) {
     alert(evt.detail.test); //alerts "Any Object Here"
}, false);

 //Dispatch an event
 var evt = document.createEvent('CustomEvent');
 evt.initCustomEvent('MyEventType', false, false, { test: "Any Object Here" });
 window.dispatchEvent(evt);