JSFiddle - React, Tailwind, and code Playground

JavaScript

var init = function(){
  var one = new Array();
  var two = new Array();

  root = new Array();
  root.push(one);
  root.push(two);

  var one_one = {'id': 1, 'name':"one_one"};
  var one_two = {'id': 2, 'name':"one_two"};

  var two_one = {'id': 3, 'name':"one_two"};
  var two_two = {'id': 1, 'name':"one_one"};

  one.push(one_one);
  one.push(one_two);

  two.push(two_one);
  two.push(two_two);
}

this.check = function(_array){
  for (var element in _array) { 
    if( Object.prototype.toString.call( _array[element] ) === '[object Array]'){
			// Found an array
      this.check(_array[element]);
    } else{
      // Found an object
      toCheck = JSON.stringify(_array[element]);
      counter = 0;

			this.checkDuplicates(root, toCheck);
			if(counter == 2){
      	console.log("duplicate found for item: " + toCheck)
      }
    }
  }
}

this.checkDuplicates = function(_array, toCheck){
  for (var element in _array) { 
    if( Object.prototype.toString.call( _array[element] ) === '[object Array]'){
			// Found an array
      this.checkDuplicates(_array[element], toCheck);
    } else{
      // Found an object
      if(JSON.stringify(_array[element]) === toCheck){
      	counter++;
      }
    }
  }
}

init();
check(root);