diff --git a/editor/libeditor/nsHTMLDataTransfer.cpp b/editor/libeditor/nsHTMLDataTransfer.cpp
index 93fd3836c3f5..381bba35dd20 100644
--- a/editor/libeditor/nsHTMLDataTransfer.cpp
+++ b/editor/libeditor/nsHTMLDataTransfer.cpp
@@ -629,8 +629,9 @@ nsHTMLEditor::DoInsertHTMLWithContext(const nsAString & aInputString,
       // but don't cross tables
       if (!nsHTMLEditUtils::IsTable(lastInsertNode))
       {
-        rv = GetLastEditableLeaf(lastInsertNode, address_of(selNode));
-        NS_ENSURE_SUCCESS(rv, rv);
+        nsCOMPtr<nsINode> lastInsertNode_ = do_QueryInterface(lastInsertNode);
+        NS_ENSURE_STATE(lastInsertNode_ || !lastInsertNode);
+        selNode = GetAsDOMNode(GetLastEditableLeaf(*lastInsertNode_));
         tmp = selNode;
         while (tmp && (tmp != lastInsertNode))
         {
diff --git a/editor/libeditor/nsHTMLEditRules.cpp b/editor/libeditor/nsHTMLEditRules.cpp
index dc070c3942f8..59449df7ea1c 100644
--- a/editor/libeditor/nsHTMLEditRules.cpp
+++ b/editor/libeditor/nsHTMLEditRules.cpp
@@ -2203,16 +2203,14 @@ nsHTMLEditRules::WillDeleteSelection(Selection* aSelection,
       if (aAction == nsIEditor::ePrevious) 
       {
         NS_ENSURE_STATE(mHTMLEditor);
-        res = mHTMLEditor->GetLastEditableLeaf( visNode, address_of(leafNode));
-        NS_ENSURE_SUCCESS(res, res);
+        leafNode = GetAsDOMNode(mHTMLEditor->GetLastEditableLeaf(*visNode_));
         leftNode = leafNode;
         rightNode = startNode;
       }
       else
       {
         NS_ENSURE_STATE(mHTMLEditor);
-        res = mHTMLEditor->GetFirstEditableLeaf( visNode, address_of(leafNode));
-        NS_ENSURE_SUCCESS(res, res);
+        leafNode = GetAsDOMNode(mHTMLEditor->GetFirstEditableLeaf(*visNode_));
         leftNode = startNode;
         rightNode = leafNode;
       }
diff --git a/editor/libeditor/nsHTMLEditor.cpp b/editor/libeditor/nsHTMLEditor.cpp
index 379864dfb051..55164ca83467 100644
--- a/editor/libeditor/nsHTMLEditor.cpp
+++ b/editor/libeditor/nsHTMLEditor.cpp
@@ -4188,71 +4188,37 @@ nsHTMLEditor::GetLastEditableChild(nsINode& aNode)
   return child;
 }
 
-nsresult 
-nsHTMLEditor::GetFirstEditableLeaf( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOutFirstLeaf)
+nsIContent*
+nsHTMLEditor::GetFirstEditableLeaf(nsINode& aNode)
 {
-  // check parms
-  nsCOMPtr<nsINode> node = do_QueryInterface(aNode);
-  NS_ENSURE_TRUE(node && aOutFirstLeaf, NS_ERROR_NULL_POINTER);
-  
-  // init out parms
-  *aOutFirstLeaf = aNode;
-  
-  // find leftmost leaf
-  nsresult res = NS_OK;
-  nsCOMPtr<nsIDOMNode> child = GetAsDOMNode(GetLeftmostChild(node));
-  while (child && (!IsEditable(child) || !nsEditorUtils::IsLeafNode(child)))
-  {
-    nsCOMPtr<nsIDOMNode> tmp;
-    res = GetNextHTMLNode(child, address_of(tmp));
-    NS_ENSURE_SUCCESS(res, res);
-    NS_ENSURE_TRUE(tmp, NS_ERROR_FAILURE);
-    
-    // only accept nodes that are descendants of aNode
-    if (nsEditorUtils::IsDescendantOf(tmp, aNode))
-      child = tmp;
-    else
-    {
-      child = nullptr;  // this will abort the loop
+  nsCOMPtr<nsIContent> child = GetLeftmostChild(&aNode);
+  while (child && (!IsEditable(child) || child->HasChildren())) {
+    child = GetNextHTMLNode(child);
+
+    // Only accept nodes that are descendants of aNode
+    if (!aNode.Contains(child)) {
+      return nullptr;
     }
   }
-  
-  *aOutFirstLeaf = child;
-  return res;
+
+  return child;
 }
 
 
-nsresult 
-nsHTMLEditor::GetLastEditableLeaf(nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOutLastLeaf)
+nsIContent*
+nsHTMLEditor::GetLastEditableLeaf(nsINode& aNode)
 {
-  // check parms
-  nsCOMPtr<nsINode> node = do_QueryInterface(aNode);
-  NS_ENSURE_TRUE(node && aOutLastLeaf, NS_ERROR_NULL_POINTER);
-  
-  // init out parms
-  *aOutLastLeaf = nullptr;
-  
-  // find rightmost leaf
-  nsCOMPtr<nsIDOMNode> child = GetAsDOMNode(GetRightmostChild(node, false));
-  nsresult res = NS_OK;
-  while (child && (!IsEditable(child) || !nsEditorUtils::IsLeafNode(child)))
-  {
-    nsCOMPtr<nsIDOMNode> tmp;
-    res = GetPriorHTMLNode(child, address_of(tmp));
-    NS_ENSURE_SUCCESS(res, res);
-    NS_ENSURE_TRUE(tmp, NS_ERROR_FAILURE);
-    
-    // only accept nodes that are descendants of aNode
-    if (nsEditorUtils::IsDescendantOf(tmp, aNode))
-      child = tmp;
-    else
-    {
-      child = nullptr;
+  nsCOMPtr<nsIContent> child = GetRightmostChild(&aNode, false);
+  while (child && (!IsEditable(child) || child->HasChildren())) {
+    child = GetPriorHTMLNode(child);
+
+    // Only accept nodes that are descendants of aNode
+    if (!aNode.Contains(child)) {
+      return nullptr;
     }
   }
-  
-  *aOutLastLeaf = child;
-  return res;
+
+  return child;
 }
 
 
diff --git a/editor/libeditor/nsHTMLEditor.h b/editor/libeditor/nsHTMLEditor.h
index 801bb6d761cd..8eda73cb0d98 100644
--- a/editor/libeditor/nsHTMLEditor.h
+++ b/editor/libeditor/nsHTMLEditor.h
@@ -715,8 +715,8 @@ protected:
   nsIContent* GetFirstEditableChild(nsINode& aNode);
   nsIContent* GetLastEditableChild(nsINode& aNode);
 
-  nsresult GetFirstEditableLeaf( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOutFirstLeaf);
-  nsresult GetLastEditableLeaf( nsIDOMNode *aNode, nsCOMPtr<nsIDOMNode> *aOutLastLeaf);
+  nsIContent* GetFirstEditableLeaf(nsINode& aNode);
+  nsIContent* GetLastEditableLeaf(nsINode& aNode);
 
   nsresult GetInlinePropertyBase(nsIAtom *aProperty, 
                              const nsAString *aAttribute,