diff --git a/editor/libeditor/base/CreateElementTxn.cpp b/editor/libeditor/base/CreateElementTxn.cpp
index f785c9ea644c..3d7ef70b60a6 100644
--- a/editor/libeditor/base/CreateElementTxn.cpp
+++ b/editor/libeditor/base/CreateElementTxn.cpp
@@ -11,13 +11,14 @@
 #include "nsIDOMElement.h"
 #include "nsReadableUtils.h"
 
-//included for new nsEditor::CreateContent()
-#include "nsIContent.h"
+#include "mozilla/dom/Element.h"
 
 #ifdef NS_DEBUG
 static bool gNoisy = false;
 #endif
 
+using namespace mozilla;
+
 CreateElementTxn::CreateElementTxn()
   : EditTxn()
 {
@@ -80,7 +81,7 @@ NS_IMETHODIMP CreateElementTxn::DoTransaction(void)
   NS_ASSERTION(mEditor && mParent, "bad state");
   NS_ENSURE_TRUE(mEditor && mParent, NS_ERROR_NOT_INITIALIZED);
 
-  nsCOMPtr<nsIContent> newContent;
+  nsCOMPtr<dom::Element> newContent;
  
   //new call to use instead to get proper HTML element, bug# 39919
   nsresult result = mEditor->CreateHTMLContent(mTag, getter_AddRefs(newContent));
diff --git a/editor/libeditor/base/nsEditor.cpp b/editor/libeditor/base/nsEditor.cpp
index e901f83bac64..4268a9da95bd 100644
--- a/editor/libeditor/base/nsEditor.cpp
+++ b/editor/libeditor/base/nsEditor.cpp
@@ -1540,7 +1540,7 @@ nsEditor::ReplaceContainer(nsIDOMNode *inNode,
   NS_ENSURE_SUCCESS(res, res);
 
   // create new container
-  nsCOMPtr<nsIContent> newContent;
+  nsCOMPtr<dom::Element> newContent;
 
   //new call to use instead to get proper HTML element, bug# 39919
   res = CreateHTMLContent(aNodeType, getter_AddRefs(newContent));
@@ -1658,7 +1658,7 @@ nsEditor::InsertContainerAbove( nsIDOMNode *inNode,
   NS_ENSURE_SUCCESS(res, res);
 
   // create new container
-  nsCOMPtr<nsIContent> newContent;
+  nsCOMPtr<dom::Element> newContent;
 
   //new call to use instead to get proper HTML element, bug# 39919
   res = CreateHTMLContent(aNodeType, getter_AddRefs(newContent));
@@ -5034,7 +5034,7 @@ nsresult nsEditor::ClearSelection()
 }
 
 nsresult
-nsEditor::CreateHTMLContent(const nsAString& aTag, nsIContent** aContent)
+nsEditor::CreateHTMLContent(const nsAString& aTag, dom::Element** aContent)
 {
   nsCOMPtr<nsIDocument> doc = GetDocument();
   NS_ENSURE_TRUE(doc, NS_ERROR_FAILURE);
@@ -5047,7 +5047,8 @@ nsEditor::CreateHTMLContent(const nsAString& aTag, nsIContent** aContent)
     return NS_ERROR_FAILURE;
   }
 
-  return doc->CreateElem(aTag, nsnull, kNameSpaceID_XHTML, aContent);
+  return doc->CreateElem(aTag, nsnull, kNameSpaceID_XHTML,
+                         reinterpret_cast<nsIContent**>(aContent));
 }
 
 nsresult
diff --git a/editor/libeditor/base/nsEditor.h b/editor/libeditor/base/nsEditor.h
index 5f3869f29701..9164ab4b5948 100644
--- a/editor/libeditor/base/nsEditor.h
+++ b/editor/libeditor/base/nsEditor.h
@@ -201,7 +201,8 @@ public:
       nsString& aTag          - tag you want
       nsIContent** aContent   - returned Content that was created with above namespace.
   */
-  nsresult CreateHTMLContent(const nsAString& aTag, nsIContent** aContent);
+  nsresult CreateHTMLContent(const nsAString& aTag,
+                             mozilla::dom::Element** aContent);
 
   // IME event handlers
   virtual nsresult BeginIMEComposition();
diff --git a/editor/libeditor/html/nsHTMLAnonymousUtils.cpp b/editor/libeditor/html/nsHTMLAnonymousUtils.cpp
index 88ab20a7077a..b6943686807e 100644
--- a/editor/libeditor/html/nsHTMLAnonymousUtils.cpp
+++ b/editor/libeditor/html/nsHTMLAnonymousUtils.cpp
@@ -27,6 +27,8 @@
 #include "nsUnicharUtils.h"
 #include "nsContentUtils.h"
 
+using namespace mozilla;
+
 // retrieve an integer stored into a CSS computed float value
 static PRInt32 GetCSSFloatValue(nsIDOMCSSStyleDeclaration * aDecl,
                                 const nsAString & aProperty)
@@ -123,7 +125,7 @@ nsHTMLEditor::CreateAnonymousElement(const nsAString & aTag, nsIDOMNode *  aPare
   NS_ENSURE_TRUE(ps, NS_ERROR_NOT_INITIALIZED);
 
   // Create a new node through the element factory
-  nsCOMPtr<nsIContent> newContent;
+  nsCOMPtr<dom::Element> newContent;
   nsresult res = CreateHTMLContent(aTag, getter_AddRefs(newContent));
   NS_ENSURE_SUCCESS(res, res);
 
diff --git a/editor/libeditor/html/nsHTMLEditor.cpp b/editor/libeditor/html/nsHTMLEditor.cpp
index c7d8e5e2e4a8..b13b5131a33c 100644
--- a/editor/libeditor/html/nsHTMLEditor.cpp
+++ b/editor/libeditor/html/nsHTMLEditor.cpp
@@ -2856,7 +2856,7 @@ nsHTMLEditor::CreateElementWithDefaults(const nsAString& aTagName, nsIDOMElement
   //  go through the transaction system
 
   nsCOMPtr<nsIDOMElement>newElement;
-  nsCOMPtr<nsIContent> newContent;
+  nsCOMPtr<dom::Element> newContent;
   nsCOMPtr<nsIDOMDocument> doc = do_QueryReferent(mDocWeak);
   NS_ENSURE_TRUE(doc, NS_ERROR_NOT_INITIALIZED);
 
diff --git a/editor/libeditor/html/nsHTMLEditorStyle.cpp b/editor/libeditor/html/nsHTMLEditorStyle.cpp
index 95f288fdfd5d..6d6f96cf6060 100644
--- a/editor/libeditor/html/nsHTMLEditorStyle.cpp
+++ b/editor/libeditor/html/nsHTMLEditorStyle.cpp
@@ -284,16 +284,16 @@ nsHTMLEditor::IsSimpleModifiableNode(nsIContent* aContent,
   // "text-decoration: underline", which decomposes into four different text-*
   // properties.  So for now, we just create a span, add the desired style, and
   // see if it matches.
-  nsCOMPtr<nsIContent> newSpan;
+  nsCOMPtr<dom::Element> newSpan;
   nsresult res = CreateHTMLContent(NS_LITERAL_STRING("span"),
                                    getter_AddRefs(newSpan));
   NS_ASSERTION(NS_SUCCEEDED(res), "CreateHTMLContent failed");
   NS_ENSURE_SUCCESS(res, false);
-  mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(newSpan->AsElement(), aProperty,
+  mHTMLCSSUtils->SetCSSEquivalentToHTMLStyle(newSpan, aProperty,
                                              aAttribute, aValue,
                                              /*suppress transaction*/ true);
 
-  return mHTMLCSSUtils->ElementsSameStyle(newSpan->AsElement(), element);
+  return mHTMLCSSUtils->ElementsSameStyle(newSpan, element);
 }
 
 
diff --git a/editor/libeditor/text/nsTextEditRules.cpp b/editor/libeditor/text/nsTextEditRules.cpp
index dbedaf32c641..2fafb2cf3bd1 100644
--- a/editor/libeditor/text/nsTextEditRules.cpp
+++ b/editor/libeditor/text/nsTextEditRules.cpp
@@ -1116,7 +1116,7 @@ nsTextEditRules::CreateBogusNodeIfNeeded(nsISelection *aSelection)
   }
 
   // Create a br.
-  nsCOMPtr<nsIContent> newContent;
+  nsCOMPtr<dom::Element> newContent;
   nsresult rv = mEditor->CreateHTMLContent(NS_LITERAL_STRING("br"), getter_AddRefs(newContent));
   NS_ENSURE_SUCCESS(rv, rv);