This is just a copy of this stackoverflow answer.
Simply copy this into browser console and call it with the issued object.
function isCyclic(obj) {
var keys = [];
var stack = [];
var stackSet = new Set();
var detected = false;
function detect(obj, key) {
if (obj && typeof obj != 'object') { return; }
if (stackSet.has(obj)) { // it's cyclic! Print the object and its locations.
var oldindex = stack.indexOf(obj);
var l1 = keys.join('.') + '.' + key;
var l2 = keys.slice(0, oldindex + 1).join('.');
console.log('CIRCULAR: ' + l1 + ' = ' + l2 + ' = ' + obj);
console.log(obj);
detected = true;
return;
}
keys.push(key);
stack.push(obj);
stackSet.add(obj);
for (var k in obj) { //dive on the object's children
if (Object.prototype.hasOwnProperty.call(obj, k)) { detect(obj[k], k); }
}
keys.pop();
stack.pop();
stackSet.delete(obj);
return;
}
detect(obj, 'obj');
return detected;
}