diff --git a/accessible/xpcom/xpcAccessibleDocument.cpp b/accessible/xpcom/xpcAccessibleDocument.cpp
index d8da3ac1e5a..601cf06fd4f 100644
--- a/accessible/xpcom/xpcAccessibleDocument.cpp
+++ b/accessible/xpcom/xpcAccessibleDocument.cpp
@@ -13,6 +13,7 @@
 #include "DocAccessible-inl.h"
 #include "nsIDOMDocument.h"
 
+using namespace mozilla;
 using namespace mozilla::a11y;
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -227,3 +228,18 @@ xpcAccessibleDocument::Shutdown()
   }
   xpcAccessibleGeneric::Shutdown();
 }
+
+xpcAccessibleGeneric*
+a11y::ToXPC(AccessibleOrProxy aAcc)
+{
+  if (aAcc.IsNull()) {
+    return nullptr;
+  }
+
+  if (aAcc.IsAccessible()) {
+    return ToXPC(aAcc.AsAccessible());
+  }
+
+ xpcAccessibleDocument* doc = ToXPCDocument(aAcc.AsProxy()->Document());
+ return doc->GetXPCAccessible(aAcc.AsProxy());
+}
diff --git a/accessible/xpcom/xpcAccessibleDocument.h b/accessible/xpcom/xpcAccessibleDocument.h
index 5b55e5dbe46..5d21683e6ad 100644
--- a/accessible/xpcom/xpcAccessibleDocument.h
+++ b/accessible/xpcom/xpcAccessibleDocument.h
@@ -118,6 +118,8 @@ ToXPC(Accessible* aAccessible)
   return xpcDoc ? xpcDoc->GetAccessible(aAccessible) : nullptr;
 }
 
+xpcAccessibleGeneric* ToXPC(AccessibleOrProxy aAcc);
+
 inline xpcAccessibleHyperText*
 ToXPCText(HyperTextAccessible* aAccessible)
 {
@@ -135,6 +137,12 @@ ToXPCDocument(DocAccessible* aAccessible)
   return GetAccService()->GetXPCDocument(aAccessible);
 }
 
+inline xpcAccessibleDocument*
+ToXPCDocument(DocAccessibleParent* aAccessible)
+{
+  return GetAccService()->GetXPCDocument(aAccessible);
+}
+
 } // namespace a11y
 } // namespace mozilla