To implement UIA on Windows going forward, we need a way to handle announcements, i.e. alerts, raised to a screen reader to narrate. If we implement UIA, which is in progress, we can achieve this by storing an implementation of IRawElementProviderSimple within AXFragmentRootWin that holds the announcement text, and can be passed as the pProvider parameter to UiaRaiseAutomationEvent(pProvider, UIA_SystemAlertEventId).