Gets the list of items in the listbox.
In Silk Test 14.0 or later, whitespace in the list is trimmed consistently across all supported browsers. For some browser versions, this whitespace handling differs to Silk Test versions prior to Silk Test 13.5. You can re-enable the old behavior by setting the OPT_COMPATIBILITY option to a version lower than 13.5.0.
'Declaration Protected Read Property Items As List(Of ItemIdentifier)