diff --git a/content/html/content/src/HTMLSharedListElement.cpp b/content/html/content/src/HTMLSharedListElement.cpp
index 87796b514f9..319557a31d4 100644
--- a/content/html/content/src/HTMLSharedListElement.cpp
+++ b/content/html/content/src/HTMLSharedListElement.cpp
@@ -32,7 +32,6 @@ NS_INTERFACE_MAP_BEGIN(HTMLSharedListElement)
   NS_HTML_CONTENT_INTERFACES_AMBIGUOUS(nsGenericHTMLElement,
                                        nsIDOMHTMLOListElement)
   NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLOListElement, ol)
-  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLDListElement, dl)
   NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLUListElement, ul)
 NS_ELEMENT_INTERFACE_MAP_END
 
diff --git a/content/html/content/src/HTMLSharedListElement.h b/content/html/content/src/HTMLSharedListElement.h
index 28b87dea013..60922653f59 100644
--- a/content/html/content/src/HTMLSharedListElement.h
+++ b/content/html/content/src/HTMLSharedListElement.h
@@ -9,7 +9,6 @@
 #include "mozilla/Util.h"
 
 #include "nsIDOMHTMLOListElement.h"
-#include "nsIDOMHTMLDListElement.h"
 #include "nsIDOMHTMLUListElement.h"
 #include "nsGenericHTMLElement.h"
 
@@ -18,7 +17,6 @@ namespace dom {
 
 class HTMLSharedListElement MOZ_FINAL : public nsGenericHTMLElement,
                                         public nsIDOMHTMLOListElement,
-                                        public nsIDOMHTMLDListElement,
                                         public nsIDOMHTMLUListElement
 {
 public:
@@ -43,9 +41,6 @@ public:
   // nsIDOMHTMLOListElement
   NS_DECL_NSIDOMHTMLOLISTELEMENT
 
-  // nsIDOMHTMLDListElement
-  // fully declared by NS_DECL_NSIDOMHTMLOLISTELEMENT
-
   // nsIDOMHTMLUListElement
   // fully declared by NS_DECL_NSIDOMHTMLOLISTELEMENT
 
diff --git a/dom/interfaces/html/moz.build b/dom/interfaces/html/moz.build
index 5daac95d720..d7655022d30 100644
--- a/dom/interfaces/html/moz.build
+++ b/dom/interfaces/html/moz.build
@@ -16,7 +16,6 @@ XPIDL_SOURCES += [
     'nsIDOMHTMLByteRanges.idl',
     'nsIDOMHTMLCanvasElement.idl',
     'nsIDOMHTMLCollection.idl',
-    'nsIDOMHTMLDListElement.idl',
     'nsIDOMHTMLDirectoryElement.idl',
     'nsIDOMHTMLDivElement.idl',
     'nsIDOMHTMLDocument.idl',
diff --git a/dom/interfaces/html/nsIDOMHTMLDListElement.idl b/dom/interfaces/html/nsIDOMHTMLDListElement.idl
deleted file mode 100644
index c17853442f4..00000000000
--- a/dom/interfaces/html/nsIDOMHTMLDListElement.idl
+++ /dev/null
@@ -1,23 +0,0 @@
-/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include "nsIDOMHTMLElement.idl"
-
-/**
- * The nsIDOMHTMLDListElement interface is the interface to a [X]HTML
- * dl element.
- *
- * This interface is trying to follow the DOM Level 2 HTML specification:
- * http://www.w3.org/TR/DOM-Level-2-HTML/
- *
- * with changes from the work-in-progress WHATWG HTML specification:
- * http://www.whatwg.org/specs/web-apps/current-work/
- */
-
-[scriptable, uuid(edd9338b-f0d5-4825-97d6-6a49862309cc)]
-interface nsIDOMHTMLDListElement : nsIDOMHTMLElement
-{
-           attribute boolean          compact;
-};