diff --git a/accessible/src/base/nsDocAccessible.cpp b/accessible/src/base/nsDocAccessible.cpp
index 6f81ecc05a07..da3829c9b02e 100644
--- a/accessible/src/base/nsDocAccessible.cpp
+++ b/accessible/src/base/nsDocAccessible.cpp
@@ -1399,7 +1399,7 @@ nsDocAccessible::CreateTextChangeEventForNode(nsIAccessible *aContainerAccessibl
     }
   }
   else {
-    NS_ASSERTION(changeAccessible == aAccessibleForChangeNode,
+    NS_ASSERTION(!changeAccessible || changeAccessible == aAccessibleForChangeNode,
                  "Hypertext is reporting a different accessible for this node");
     length = TextLength(aAccessibleForChangeNode);
     if (Role(aAccessibleForChangeNode) == nsIAccessibleRole::ROLE_WHITESPACE) {  // newline