Chrome

In order to see all browser events in real time, enter in the browser console monitorEvents(tempVar, 'events type')

tempVar - temp variable that you need to create in devtools (right clikc on any node > store as global variable).

You can just find a node. For example monitorEvents(document.body, 'mouse').

events type - event type, for example ‘mouse’. Or specific event

Firefox

There is no native function in Firefox. But you can create it!

function monitorEvents(element) {
  let log = function(e) { console.log(e);};
  let events = [];

  for(let i in element) {
    if(i.startsWith("on")) events.push(i.substr(2));
  }
  events.forEach(function(eventName) {
    element.addEventListener(eventName, log);
  });
}

Then run with the node as argument. For example monitorEvents(temp0) or monitorEvents(document.body).

Advice from stackoverflow: If you’re trying to see all the events are happening inside an element (such as the body), you should log during the capture phase - element.addEventListener(eventName, log, true);