Javascript debugging helper – Count number of eventlisteners in Chrome console

Paste and run one of the code blocks below in chrome console to get eventlisteners count.

//eventlisteners counter - grouped summary
Array.from(document.querySelectorAll('*'))  .reduce(function(pre, dom){
    var evtObj = getEventListeners(dom)
    Object.keys(evtObj).forEach(function (evt) {
      if (typeof pre[evt] === 'undefined') {
        pre[evt] = 0
      }
      pre[evt] += evtObj[evt].length
    })
    return pre
  }, {})
  
//_-------------------------------------------
  
  // //eventlisteners - totalcount
  var totalCount = 0;
  Array.from(document.querySelectorAll('*')).reduce(function(pre, dom){
    var evtObj = getEventListeners(dom)
    Object.keys(evtObj).forEach(function (evt) {
      if (typeof pre[evt] === 'undefined') {
        pre[evt] = 0
      }
      // pre[evt] += evtObj[evt].length
	  totalCount += evtObj[evt].length;
    })
    return totalCount;
  }, {})
  
  
  //---------------------------------------

 

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