1 files changed, 6 insertions, 0 deletions
diff --git a/dom/base/FragmentOrElement.cpp b/dom/base/FragmentOrElement.cpp
index fde983e7c..13ba19c8c 100644
--- a/dom/base/FragmentOrElement.cpp
+++ b/dom/base/FragmentOrElement.cpp
@@ -585,6 +585,12 @@ FragmentOrElement::nsDOMSlots::Traverse(nsCycleCollectionTraversalCallback &cb,
       mCustomElementData->mCallbackQueue[i]->Traverse(cb);
     }
   }
+
+  for (auto iter = mRegisteredIntersectionObservers.Iter(); !iter.Done(); iter.Next()) {
+    DOMIntersectionObserver* observer = iter.Key();
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mSlots->mRegisteredIntersectionObservers[i]");
+    cb.NoteXPCOMChild(observer);
+  }
 }
 
 void