2.1.1 [W3C-WEBSTG2] Section 4.1 The Storage interface

V0001: The getItem method returns any type, not a nullable DOMString

The specification states:

 4.1 The Storage interface
  
     IDLinterface Storage {
         ...
         getter DOMString? getItem(DOMString key);
         ...
     };

All document modes (All versions)

The getItem method returns any type, not a nullable DOMString.