If `thing` contains any cycles then it will explode. E.g. const thing = {}; thing.self = thing; or const thing = []; thing.push(thing); If t

If `thing` contains any cycles then it will explode. E.g. const thing = {}; thing.self = thing; or const thing = []; thing.push(thing); If this sounds far-fetched to you just know that all DOM elements have these circular references through (for example) parent / child references. Also any non-enumerable properties that may have been defined on objects are lost. Basically the function is only suitable for recently parsed JSON.