diff --git a/accessible/windows/msaa/AccessibleWrap.cpp b/accessible/windows/msaa/AccessibleWrap.cpp
index 0b06677ec3a..30d8994cfe5 100644
--- a/accessible/windows/msaa/AccessibleWrap.cpp
+++ b/accessible/windows/msaa/AccessibleWrap.cpp
@@ -1199,6 +1199,41 @@ AccessibleWrap::GetNativeInterface(void** aOutAccessible)
   NS_ADDREF_THIS();
 }
 
+void
+AccessibleWrap::FireWinEvent(Accessible* aTarget, uint32_t aEventType)
+{
+  static_assert(sizeof(gWinEventMap)/sizeof(gWinEventMap[0]) == nsIAccessibleEvent::EVENT_LAST_ENTRY,
+                "MSAA event map skewed");
+
+  NS_ASSERTION(aEventType > 0 && aEventType < ArrayLength(gWinEventMap), "invalid event type");
+
+  uint32_t winEvent = gWinEventMap[aEventType];
+  if (!winEvent)
+    return;
+
+  int32_t childID = GetChildIDFor(aTarget);
+  if (!childID)
+    return; // Can't fire an event without a child ID
+
+  HWND hwnd = GetHWNDFor(aTarget);
+  if (!hwnd) {
+    return;
+  }
+
+  // Fire MSAA event for client area window.
+  ::NotifyWinEvent(winEvent, hwnd, OBJID_CLIENT, childID);
+
+  // JAWS announces collapsed combobox navigation based on focus events.
+  if (aEventType == nsIAccessibleEvent::EVENT_SELECTION &&
+      Compatibility::IsJAWS()) {
+    roles::Role role = aTarget->IsProxy() ? aTarget->Proxy()->Role() :
+      aTarget->Role();
+    if (role == roles::COMBOBOX_OPTION) {
+      ::NotifyWinEvent(EVENT_OBJECT_FOCUS, hwnd, OBJID_CLIENT, childID);
+    }
+  }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Accessible
 
@@ -1214,15 +1249,6 @@ AccessibleWrap::HandleAccEvent(AccEvent* aEvent)
 
   uint32_t eventType = aEvent->GetEventType();
 
-  static_assert(sizeof(gWinEventMap)/sizeof(gWinEventMap[0]) == nsIAccessibleEvent::EVENT_LAST_ENTRY,
-                "MSAA event map skewed");
-
-  NS_ENSURE_TRUE(eventType > 0 && eventType < ArrayLength(gWinEventMap), NS_ERROR_FAILURE);
-
-  uint32_t winEvent = gWinEventMap[eventType];
-  if (!winEvent)
-    return NS_OK;
-
   // Means we're not active.
   NS_ENSURE_TRUE(!IsDefunct(), NS_ERROR_FAILURE);
 
@@ -1235,23 +1261,7 @@ AccessibleWrap::HandleAccEvent(AccEvent* aEvent)
     UpdateSystemCaretFor(accessible);
   }
 
-  int32_t childID = GetChildIDFor(accessible); // get the id for the accessible
-  if (!childID)
-    return NS_OK; // Can't fire an event without a child ID
-
-  HWND hWnd = GetHWNDFor(accessible);
-  NS_ENSURE_TRUE(hWnd, NS_ERROR_FAILURE);
-
-  // Fire MSAA event for client area window.
-  ::NotifyWinEvent(winEvent, hWnd, OBJID_CLIENT, childID);
-
-  // JAWS announces collapsed combobox navigation based on focus events.
-  if (Compatibility::IsJAWS()) {
-    if (eventType == nsIAccessibleEvent::EVENT_SELECTION &&
-      accessible->Role() == roles::COMBOBOX_OPTION) {
-      ::NotifyWinEvent(EVENT_OBJECT_FOCUS, hWnd, OBJID_CLIENT, childID);
-    }
-  }
+  FireWinEvent(accessible, eventType);
 
   return NS_OK;
 }
diff --git a/accessible/windows/msaa/AccessibleWrap.h b/accessible/windows/msaa/AccessibleWrap.h
index 771dad5a02c..fc0b8bedab3 100644
--- a/accessible/windows/msaa/AccessibleWrap.h
+++ b/accessible/windows/msaa/AccessibleWrap.h
@@ -159,6 +159,8 @@ public: // construction, destruction
   static int32_t GetChildIDFor(Accessible* aAccessible);
   static HWND GetHWNDFor(Accessible* aAccessible);
 
+  static void FireWinEvent(Accessible* aTarget, uint32_t aEventType);
+
   /**
    * System caret support: update the Windows caret position. 
    * The system caret works more universally than the MSAA caret