The HTML5 Microdata DOM API has been implemented, adding the
getItems property to the
Document interface as well as the
properties properties to the
If you’d like to add custom data to each element, it should be safer to use the
HTMLElement.dataset property rather than arbitrary properties. Firefox has also implemented the
getUserData methods that allow storing non-string data. However, those methods have been deprecated in favour of the
Update: The Microdata API support has been removed with Firefox 49.