Looks like you want to access a user defined property, since these are not properties of the DOM ( Firebug Wiki DOM panel page. ), I don't think you can access them directly through your page, but you can access them through the Firebug console.
Simply type the name of the property into the command line of the Console
... the part after >>>
on the very bottom.
In your case you would type something like: sitems[0]
and hit enter.
To access properties of the DOM... take a look at the DOM exploration page for Firebug.
To see how to access properties, functions, or constants of the DOM, check what you're interested in in the DOM tab.
Then you can "follow the bread crumbs" to access properties directly. Global properties are attached to window
, so you don't need to include window
:
Make sure to right click on things and explore the context menu, especially if you start looking at functions.