This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.
Otherwise insert, change and remove ARIA via scripting. For instance, a collapsed section of a tree widget might look like this: <li role=treeitem aria-expanded=false ... When the user opens the section, it is changed to this using JavaScript : <li role=treeitem aria-expanded=true ...