diff --git a/editor/libeditor/text/nsTextEditRules.cpp b/editor/libeditor/text/nsTextEditRules.cpp
index d6ea49e405e..9180ad2a60a 100644
--- a/editor/libeditor/text/nsTextEditRules.cpp
+++ b/editor/libeditor/text/nsTextEditRules.cpp
@@ -1052,52 +1052,36 @@ nsTextEditRules::RemoveRedundantTrailingBR()
   if (IsSingleLineEditor())
     return NS_OK;
 
-  nsCOMPtr<nsIDOMNode> body = do_QueryInterface(mEditor->GetRoot());
+  nsRefPtr<dom::Element> body = mEditor->GetRoot();
   if (!body)
     return NS_ERROR_NULL_POINTER;
 
-  bool hasChildren;
-  nsresult res = body->HasChildNodes(&hasChildren);
-  NS_ENSURE_SUCCESS(res, res);
-
-  if (hasChildren) {
-    nsCOMPtr<nsIDOMNodeList> childList;
-    res = body->GetChildNodes(getter_AddRefs(childList));
-    NS_ENSURE_SUCCESS(res, res);
-
-    if (!childList)
-      return NS_ERROR_NULL_POINTER;
-
-    PRUint32 childCount;
-    res = childList->GetLength(&childCount);
-    NS_ENSURE_SUCCESS(res, res);
-
+  PRUint32 childCount = body->GetChildCount();
+  if (childCount > 1) {
     // The trailing br is redundant if it is the only remaining child node
-    if (childCount != 1)
-      return NS_OK;
-
-    nsCOMPtr<nsIDOMNode> child;
-    res = body->GetFirstChild(getter_AddRefs(child));
-    NS_ENSURE_SUCCESS(res, res);
-
-    if (nsTextEditUtils::IsMozBR(child)) {
-      // Rather than deleting this node from the DOM tree we should instead
-      // morph this br into the bogus node
-      nsCOMPtr<nsIDOMElement> elem = do_QueryInterface(child);
-      if (elem) {
-        elem->RemoveAttribute(NS_LITERAL_STRING("type"));
-        NS_ENSURE_SUCCESS(res, res);
-
-        // set mBogusNode to be this <br>
-        mBogusNode = elem;
- 
-        // give it the bogus node attribute
-        nsCOMPtr<nsIContent> content = do_QueryInterface(elem);
-        content->SetAttr(kNameSpaceID_None, kMOZEditorBogusNodeAttrAtom,
-                         kMOZEditorBogusNodeValue, false);
-      }
-    }
+    return NS_OK;
   }
+
+  nsRefPtr<nsIContent> child = body->GetFirstChild();
+  if (!child || !child->IsElement()) {
+    return NS_OK;
+  }
+
+  dom::Element* elem = child->AsElement();
+  if (!nsTextEditUtils::IsMozBR(elem)) {
+    return NS_OK;
+  }
+
+  // Rather than deleting this node from the DOM tree we should instead
+  // morph this br into the bogus node
+  elem->UnsetAttr(kNameSpaceID_None, nsGkAtoms::type, true);
+
+  // set mBogusNode to be this <br>
+  mBogusNode = do_QueryInterface(elem);
+
+  // give it the bogus node attribute
+  elem->SetAttr(kNameSpaceID_None, kMOZEditorBogusNodeAttrAtom,
+                kMOZEditorBogusNodeValue, false);
   return NS_OK;
 }
 
diff --git a/editor/libeditor/text/nsTextEditUtils.cpp b/editor/libeditor/text/nsTextEditUtils.cpp
index edbb0fbc8a7..71b0bc70090 100644
--- a/editor/libeditor/text/nsTextEditUtils.cpp
+++ b/editor/libeditor/text/nsTextEditUtils.cpp
@@ -37,10 +37,14 @@
 
 #include "nsTextEditUtils.h"
 
+#include "mozilla/dom/Element.h"
+
 #include "nsEditor.h"
 #include "nsPlaintextEditor.h"
 #include "nsEditProperty.h"
 
+using namespace mozilla;
+
 ///////////////////////////////////////////////////////////////////////////
 // IsBody: true if node an html body node
 //                  
@@ -72,11 +76,19 @@ bool
 nsTextEditUtils::IsMozBR(nsIDOMNode *node)
 {
   NS_PRECONDITION(node, "null node passed to nsHTMLEditUtils::IsMozBR");
-  if (IsBreak(node) && HasMozAttr(node)) return true;
-  return false;
+  return IsBreak(node) && HasMozAttr(node);
 }
 
 
+bool
+nsTextEditUtils::IsMozBR(dom::Element* aNode)
+{
+  MOZ_ASSERT(aNode);
+  return aNode->IsHTML(nsGkAtoms::br) &&
+         aNode->AttrValueIs(kNameSpaceID_None, nsGkAtoms::type,
+                            NS_LITERAL_STRING("_moz"), eIgnoreCase);
+}
+
 ///////////////////////////////////////////////////////////////////////////
 // HasMozAttr: true if node has type attribute = _moz
 //             (used to indicate the div's and br's we use in
diff --git a/editor/libeditor/text/nsTextEditUtils.h b/editor/libeditor/text/nsTextEditUtils.h
index ce796603a8f..5dfa7eddcc8 100644
--- a/editor/libeditor/text/nsTextEditUtils.h
+++ b/editor/libeditor/text/nsTextEditUtils.h
@@ -38,37 +38,40 @@
 #ifndef nsTextEditUtils_h__
 #define nsTextEditUtils_h__
 
-#include "prtypes.h"  // for bool
 #include "nsError.h"  // for nsresult
-#include "nsString.h" // for nsAString
+
+namespace mozilla {
+namespace dom {
+class Element;
+} // namespace dom
+} // namespace mozilla
+
 class nsIDOMNode;
-class nsIEditor;
 class nsPlaintextEditor;
 
 class nsTextEditUtils
 {
 public:
   // from nsTextEditRules:
-  static bool IsBody(nsIDOMNode *aNode);
-  static bool IsBreak(nsIDOMNode *aNode);
-  static bool IsMozBR(nsIDOMNode *aNode);
-  static bool HasMozAttr(nsIDOMNode *aNode);
+  static bool IsBody(nsIDOMNode* aNode);
+  static bool IsBreak(nsIDOMNode* aNode);
+  static bool IsMozBR(nsIDOMNode* aNode);
+  static bool IsMozBR(mozilla::dom::Element* aNode);
+  static bool HasMozAttr(nsIDOMNode* aNode);
 };
 
 /***************************************************************************
  * stack based helper class for detecting end of editor initialization, in
- * order to triger "end of init" initialization of the edit rules.
+ * order to trigger "end of init" initialization of the edit rules.
  */
 class nsAutoEditInitRulesTrigger
 {
-  private:
-    nsPlaintextEditor *mEd;
-    nsresult &mRes;
-  public:
-  nsAutoEditInitRulesTrigger( nsPlaintextEditor *aEd, nsresult &aRes);
+private:
+  nsPlaintextEditor* mEd;
+  nsresult& mRes;
+public:
+  nsAutoEditInitRulesTrigger(nsPlaintextEditor* aEd, nsresult& aRes);
   ~nsAutoEditInitRulesTrigger();
 };
 
-
 #endif /* nsTextEditUtils_h__ */
-