diff --git a/dom/fetch/Headers.cpp b/dom/fetch/Headers.cpp
index d814748bea87..9c29a5434187 100644
--- a/dom/fetch/Headers.cpp
+++ b/dom/fetch/Headers.cpp
@@ -25,8 +25,8 @@ NS_INTERFACE_MAP_END
 // static
 already_AddRefed<Headers> Headers::Constructor(
     const GlobalObject& aGlobal,
-    const Optional<
-        HeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord>& aInit,
+    const Optional<ByteStringSequenceSequenceOrByteStringByteStringRecord>&
+        aInit,
     ErrorResult& aRv) {
   RefPtr<InternalHeaders> ih = new InternalHeaders();
   RefPtr<Headers> headers = new Headers(aGlobal.GetAsSupports(), ih);
@@ -35,9 +35,7 @@ already_AddRefed<Headers> Headers::Constructor(
     return headers.forget();
   }
 
-  if (aInit.Value().IsHeaders()) {
-    ih->Fill(*aInit.Value().GetAsHeaders().mInternalHeaders, aRv);
-  } else if (aInit.Value().IsByteStringSequenceSequence()) {
+  if (aInit.Value().IsByteStringSequenceSequence()) {
     ih->Fill(aInit.Value().GetAsByteStringSequenceSequence(), aRv);
   } else if (aInit.Value().IsByteStringByteStringRecord()) {
     ih->Fill(aInit.Value().GetAsByteStringByteStringRecord(), aRv);
@@ -53,8 +51,7 @@ already_AddRefed<Headers> Headers::Constructor(
 // static
 already_AddRefed<Headers> Headers::Constructor(
     const GlobalObject& aGlobal,
-    const OwningHeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord&
-        aInit,
+    const OwningByteStringSequenceSequenceOrByteStringByteStringRecord& aInit,
     ErrorResult& aRv) {
   nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(aGlobal.GetAsSupports());
   return Create(global, aInit, aRv);
@@ -63,15 +60,12 @@ already_AddRefed<Headers> Headers::Constructor(
 /* static */
 already_AddRefed<Headers> Headers::Create(
     nsIGlobalObject* aGlobal,
-    const OwningHeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord&
-        aInit,
+    const OwningByteStringSequenceSequenceOrByteStringByteStringRecord& aInit,
     ErrorResult& aRv) {
   RefPtr<InternalHeaders> ih = new InternalHeaders();
   RefPtr<Headers> headers = new Headers(aGlobal, ih);
 
-  if (aInit.IsHeaders()) {
-    ih->Fill(*(aInit.GetAsHeaders().get()->mInternalHeaders), aRv);
-  } else if (aInit.IsByteStringSequenceSequence()) {
+  if (aInit.IsByteStringSequenceSequence()) {
     ih->Fill(aInit.GetAsByteStringSequenceSequence(), aRv);
   } else if (aInit.IsByteStringByteStringRecord()) {
     ih->Fill(aInit.GetAsByteStringByteStringRecord(), aRv);
diff --git a/dom/fetch/Headers.h b/dom/fetch/Headers.h
index ab219c9f5bd9..fdccb1540619 100644
--- a/dom/fetch/Headers.h
+++ b/dom/fetch/Headers.h
@@ -22,8 +22,8 @@ namespace dom {
 
 template <typename K, typename V>
 class Record;
-class HeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord;
-class OwningHeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord;
+class ByteStringSequenceSequenceOrByteStringByteStringRecord;
+class OwningByteStringSequenceSequenceOrByteStringByteStringRecord;
 
 /**
  * This Headers class is only used to represent the content facing Headers
@@ -53,21 +53,18 @@ class Headers final : public nsISupports, public nsWrapperCache {
 
   static already_AddRefed<Headers> Constructor(
       const GlobalObject& aGlobal,
-      const Optional<
-          HeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord>&
+      const Optional<ByteStringSequenceSequenceOrByteStringByteStringRecord>&
           aInit,
       ErrorResult& aRv);
 
   static already_AddRefed<Headers> Constructor(
       const GlobalObject& aGlobal,
-      const OwningHeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord&
-          aInit,
+      const OwningByteStringSequenceSequenceOrByteStringByteStringRecord& aInit,
       ErrorResult& aRv);
 
   static already_AddRefed<Headers> Create(
       nsIGlobalObject* aGlobalObject,
-      const OwningHeadersOrByteStringSequenceSequenceOrByteStringByteStringRecord&
-          aInit,
+      const OwningByteStringSequenceSequenceOrByteStringByteStringRecord& aInit,
       ErrorResult& aRv);
 
   void Append(const nsACString& aName, const nsACString& aValue,
diff --git a/dom/webidl/Headers.webidl b/dom/webidl/Headers.webidl
index fb90b87e2e10..c492cb3c35ee 100644
--- a/dom/webidl/Headers.webidl
+++ b/dom/webidl/Headers.webidl
@@ -8,7 +8,7 @@
  * http://fetch.spec.whatwg.org/#headers-class
  */
 
-typedef (Headers or sequence<sequence<ByteString>> or record<ByteString, ByteString>) HeadersInit;
+typedef (sequence<sequence<ByteString>> or record<ByteString, ByteString>) HeadersInit;
 
 enum HeadersGuardEnum {
   "none",
diff --git a/testing/web-platform/meta/fetch/api/headers/headers-basic.html.ini b/testing/web-platform/meta/fetch/api/headers/headers-basic.html.ini
deleted file mode 100644
index b086de3d2c5e..000000000000
--- a/testing/web-platform/meta/fetch/api/headers/headers-basic.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[headers-basic.html]
-  [Create headers with existing headers with custom iterator]
-    expected: FAIL
-