HistoryStates
Description
The history state objects associated with the document.
Properties
| length readonly | Number of elements in the collection. | 
| parent readonly | The object’s container. | 
| typename readonly | The class name of the object. | 
 
Methods
| [] readonly | Get an element in the collection with the provided index. | 
| getByName readonly | Get the first element in the collection with the provided name. |