--- a/content/base/src/nsRange.cpp
+++ b/content/base/src/nsRange.cpp
@@ -385,17 +385,17 @@ nsIRange::RegisterCommonAncestor(nsINode
 
   MarkDescendants(aNode);
 
   RangeHashTable* ranges =
     static_cast<RangeHashTable*>(aNode->GetProperty(nsGkAtoms::range));
   if (!ranges) {
     ranges = new RangeHashTable;
     ranges->Init();
-    aNode->SetProperty(nsGkAtoms::range, ranges, RangeHashTableDtor);
+    aNode->SetProperty(nsGkAtoms::range, ranges, RangeHashTableDtor, true);
   }
   ranges->PutEntry(this);
   aNode->SetCommonAncestorForRangeInSelection();
 }
 
 void
 nsIRange::UnregisterCommonAncestor(nsINode* aNode)
 {