diff --git a/content/base/src/DOMImplementation.cpp b/content/base/src/DOMImplementation.cpp
index fb12d8d4a983..52c73e8a1429 100644
--- a/content/base/src/DOMImplementation.cpp
+++ b/content/base/src/DOMImplementation.cpp
@@ -211,20 +211,22 @@ DOMImplementation::CreateHTMLDocument(const nsAString& aTitle,
   rv = root->AppendChildTo(head, false);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  nsCOMPtr<nsIContent> title;
-  rv = doc->CreateElem(NS_LITERAL_STRING("title"), nullptr, kNameSpaceID_XHTML,
-                       getter_AddRefs(title));
-  NS_ENSURE_SUCCESS(rv, rv);
-  rv = head->AppendChildTo(title, false);
-  NS_ENSURE_SUCCESS(rv, rv);
+  if (!DOMStringIsNull(aTitle)) {
+    nsCOMPtr<nsIContent> title;
+    rv = doc->CreateElem(NS_LITERAL_STRING("title"), nullptr,
+                         kNameSpaceID_XHTML, getter_AddRefs(title));
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = head->AppendChildTo(title, false);
+    NS_ENSURE_SUCCESS(rv, rv);
 
-  nsCOMPtr<nsIContent> titleText;
-  rv = NS_NewTextNode(getter_AddRefs(titleText), doc->NodeInfoManager());
-  NS_ENSURE_SUCCESS(rv, rv);
-  rv = titleText->SetText(aTitle, false);
-  NS_ENSURE_SUCCESS(rv, rv);
-  rv = title->AppendChildTo(titleText, false);
-  NS_ENSURE_SUCCESS(rv, rv);
+    nsCOMPtr<nsIContent> titleText;
+    rv = NS_NewTextNode(getter_AddRefs(titleText), doc->NodeInfoManager());
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = titleText->SetText(aTitle, false);
+    NS_ENSURE_SUCCESS(rv, rv);
+    rv = title->AppendChildTo(titleText, false);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
 
   nsCOMPtr<nsIContent> body;
   rv = doc->CreateElem(NS_LITERAL_STRING("body"), nullptr, kNameSpaceID_XHTML,
@@ -241,12 +243,14 @@ DOMImplementation::CreateHTMLDocument(const nsAString& aTitle,
 }
 
 already_AddRefed<nsIDocument>
-DOMImplementation::CreateHTMLDocument(const nsAString& aTitle,
+DOMImplementation::CreateHTMLDocument(const Optional<nsAString>& aTitle,
                                       ErrorResult& aRv)
 {
   nsCOMPtr<nsIDocument> document;
   nsCOMPtr<nsIDOMDocument> domDocument;
-  aRv = CreateHTMLDocument(aTitle, getter_AddRefs(document),
+  aRv = CreateHTMLDocument(aTitle.WasPassed() ? aTitle.Value()
+                                              : NullString(),
+                           getter_AddRefs(document),
                            getter_AddRefs(domDocument));
   return document.forget();
 }
diff --git a/content/base/src/DOMImplementation.h b/content/base/src/DOMImplementation.h
index 28b6673dd314..bf6b4ab3c6f6 100644
--- a/content/base/src/DOMImplementation.h
+++ b/content/base/src/DOMImplementation.h
@@ -73,7 +73,7 @@ public:
                  ErrorResult& aRv);
 
   already_AddRefed<nsIDocument>
-  CreateHTMLDocument(const nsAString& aTitle, ErrorResult& aRv);
+  CreateHTMLDocument(const Optional<nsAString>& aTitle, ErrorResult& aRv);
 
 private:
   nsresult CreateDocument(const nsAString& aNamespaceURI,
diff --git a/dom/imptests/failures/webapps/DOMCore/tests/approved/test_interfaces.html.json b/dom/imptests/failures/webapps/DOMCore/tests/approved/test_interfaces.html.json
index fc7c5d1d4524..6961d4a9eba8 100644
--- a/dom/imptests/failures/webapps/DOMCore/tests/approved/test_interfaces.html.json
+++ b/dom/imptests/failures/webapps/DOMCore/tests/approved/test_interfaces.html.json
@@ -63,7 +63,6 @@
   "Document interface: calling prepend(union) on xmlDoc with too few arguments must throw TypeError": true,
   "Document interface: xmlDoc must inherit property \"append\" with the proper type (29)": true,
   "Document interface: calling append(union) on xmlDoc with too few arguments must throw TypeError": true,
-  "DOMImplementation interface: operation createHTMLDocument(DOMString)": true,
   "DocumentFragment interface: attribute children": true,
   "DocumentFragment interface: attribute firstElementChild": true,
   "DocumentFragment interface: attribute lastElementChild": true,
diff --git a/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/Makefile.in b/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/Makefile.in
index 324622368dc4..c54065605978 100644
--- a/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/Makefile.in
+++ b/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/Makefile.in
@@ -11,7 +11,6 @@ include $(DEPTH)/config/autoconf.mk
 
 MOCHITEST_FILES := \
   test_CharacterData-remove.html.json \
-  test_DOMImplementation-createHTMLDocument.html.json \
   test_Document-createElementNS.html.json \
   test_Document-getElementsByTagName.html.json \
   test_DocumentType-remove.html.json \
diff --git a/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/test_DOMImplementation-createHTMLDocument.html.json b/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/test_DOMImplementation-createHTMLDocument.html.json
deleted file mode 100644
index 93ba2a326ab5..000000000000
--- a/dom/imptests/failures/webapps/DOMCore/tests/submissions/Ms2ger/test_DOMImplementation-createHTMLDocument.html.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "Missing title argument": true
-}
diff --git a/dom/webidl/DOMImplementation.webidl b/dom/webidl/DOMImplementation.webidl
index e3021a9233f9..f7fa91c422ad 100644
--- a/dom/webidl/DOMImplementation.webidl
+++ b/dom/webidl/DOMImplementation.webidl
@@ -23,5 +23,5 @@ interface DOMImplementation {
                           [TreatNullAs=EmptyString] DOMString qualifiedName,
                           DocumentType? doctype);
   [Throws]
-  Document createHTMLDocument(DOMString title);
+  Document createHTMLDocument(optional DOMString title);
 };