--- a/dom/base/Crypto.cpp
+++ b/dom/base/Crypto.cpp
@@ -17,39 +17,32 @@
 using mozilla::dom::ContentChild;
 
 namespace mozilla {
 namespace dom {
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(Crypto)
   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
   NS_INTERFACE_MAP_ENTRY(nsISupports)
-  NS_INTERFACE_MAP_ENTRY(nsIDOMCrypto)
 NS_INTERFACE_MAP_END
 
 NS_IMPL_CYCLE_COLLECTING_ADDREF(Crypto)
 NS_IMPL_CYCLE_COLLECTING_RELEASE(Crypto)
 
 NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(Crypto, mParent, mSubtle)
 
-Crypto::Crypto()
+Crypto::Crypto(nsIGlobalObject* aParent)
+  : mParent(aParent)
 {
 }
 
 Crypto::~Crypto()
 {
 }
 
-void
-Crypto::Init(nsIGlobalObject* aParent)
-{
-  mParent = do_QueryInterface(aParent);
-  MOZ_ASSERT(mParent);
-}
-
 /* virtual */ JSObject*
 Crypto::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
 {
   return CryptoBinding::Wrap(aCx, this, aGivenProto);
 }
 
 void
 Crypto::GetRandomValues(JSContext* aCx, const ArrayBufferView& aArray,

--- a/dom/base/Crypto.h
+++ b/dom/base/Crypto.h
@@ -1,55 +1,48 @@
 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
 /* 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/. */
 #ifndef mozilla_dom_Crypto_h
 #define mozilla_dom_Crypto_h
 
-#include "nsIDOMCrypto.h"
 #include "mozilla/dom/SubtleCrypto.h"
 #include "nsIGlobalObject.h"
 
 #include "nsWrapperCache.h"
 #include "mozilla/dom/TypedArray.h"
-#define NS_DOMCRYPTO_CID \
-  {0x929d9320, 0x251e, 0x11d4, { 0x8a, 0x7c, 0x00, 0x60, 0x08, 0xc8, 0x44, 0xc3} }
 
 namespace mozilla {
 
 class ErrorResult;
 
 namespace dom {
 
-class Crypto : public nsIDOMCrypto,
-               public nsWrapperCache
+class Crypto final : public nsISupports,
+                     public nsWrapperCache
 {
 protected:
   virtual ~Crypto();
 
 public:
-  Crypto();
-
-  NS_DECL_NSIDOMCRYPTO
+  explicit Crypto(nsIGlobalObject* aParent);
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(Crypto)
 
   void
   GetRandomValues(JSContext* aCx, const ArrayBufferView& aArray,
                   JS::MutableHandle<JSObject*> aRetval,
                   ErrorResult& aRv);
 
   SubtleCrypto*
   Subtle();
 
-  // WebIDL
-
   nsIGlobalObject*
   GetParentObject() const
   {
     return mParent;
   }
 
   virtual JSObject*
   WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;

--- a/dom/base/nsGlobalWindowInner.cpp
+++ b/dom/base/nsGlobalWindowInner.cpp
@@ -3028,18 +3028,17 @@ nsGlobalWindowInner::GetApplicationCache
   dummy.SuppressException();
   return applicationCache.forget();
 }
 
 Crypto*
 nsGlobalWindowInner::GetCrypto(ErrorResult& aError)
 {
   if (!mCrypto) {
-    mCrypto = new Crypto();
-    mCrypto->Init(this);
+    mCrypto = new Crypto(this);
   }
   return mCrypto;
 }
 
 mozilla::dom::U2F*
 nsGlobalWindowInner::GetU2f(ErrorResult& aError)
 {
   if (!mU2F) {

--- a/dom/bindings/Bindings.conf
+++ b/dom/bindings/Bindings.conf
@@ -1707,18 +1707,16 @@ addExternalIface('MozObserver', nativeTy
 addExternalIface('MozRDFCompositeDataSource', nativeType='nsIRDFCompositeDataSource',
                  notflattened=True)
 addExternalIface('MozRDFResource', nativeType='nsIRDFResource', notflattened=True)
 addExternalIface('MozTreeView', nativeType='nsITreeView',
                   headerFile='nsITreeView.h', notflattened=True)
 addExternalIface('MozWakeLockListener', headerFile='nsIDOMWakeLockListener.h')
 addExternalIface('nsIBrowserDOMWindow', nativeType='nsIBrowserDOMWindow',
                  notflattened=True)
-addExternalIface('nsIDOMCrypto', nativeType='nsIDOMCrypto',
-                 headerFile='Crypto.h')
 addExternalIface('nsIFile', nativeType='nsIFile', notflattened=True)
 addExternalIface('nsILoadGroup', nativeType='nsILoadGroup',
                  headerFile='nsILoadGroup.h', notflattened=True)
 addExternalIface('nsIMessageBroadcaster', nativeType='nsIMessageBroadcaster',
                  headerFile='nsIMessageManager.h', notflattened=True)
 addExternalIface('nsIMessageSender', nativeType='nsIMessageSender',
                  headerFile='nsIMessageManager.h', notflattened=True)
 addExternalIface('nsIPrintSettings', nativeType='nsIPrintSettings',

--- a/dom/interfaces/base/domstubs.idl
+++ b/dom/interfaces/base/domstubs.idl
@@ -50,11 +50,8 @@ interface nsIDOMEventTarget;
 interface nsIDOMEventListener;
 
 // HTML
 interface nsIDOMHTMLFormElement;
 interface nsIDOMHTMLHeadElement;
 
 // Range
 interface nsIDOMRange;
-
-// Crypto
-interface nsIDOMCrypto;

--- a/dom/interfaces/base/moz.build
+++ b/dom/interfaces/base/moz.build
@@ -14,17 +14,16 @@ XPIDL_SOURCES += [
     'nsIContentPermissionPrompt.idl',
     'nsIContentPrefService2.idl',
     'nsIContentProcess.idl',
     'nsIContentURIGrouper.idl',
     'nsIDOMChromeWindow.idl',
     'nsIDOMClientRect.idl',
     'nsIDOMClientRectList.idl',
     'nsIDOMConstructor.idl',
-    'nsIDOMCrypto.idl',
     'nsIDOMGlobalPropertyInitializer.idl',
     'nsIDOMHistory.idl',
     'nsIDOMModalContentWindow.idl',
     'nsIDOMScreen.idl',
     'nsIDOMWindow.idl',
     'nsIDOMWindowCollection.idl',
     'nsIDOMWindowUtils.idl',
     'nsIFocusManager.idl',

deleted file mode 100644
--- a/dom/interfaces/base/nsIDOMCrypto.idl
+++ /dev/null
@@ -1,14 +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 "nsISupports.idl"
-
-interface nsIGlobalObject;
-
-[uuid(48d7f7fd-bb85-4c04-9b8b-5cd9131acdef)]
-interface nsIDOMCrypto : nsISupports
-{
-  [notxpcom] void init(in nsIGlobalObject parent);
-};

--- a/dom/webidl/Window.webidl
+++ b/dom/webidl/Window.webidl
@@ -18,17 +18,16 @@
  * https://webaudio.github.io/web-audio-api/#widl-Window-audioWorklet
  * https://drafts.css-houdini.org/css-paint-api-1/#dom-window-paintworklet
  */
 
 interface ApplicationCache;
 interface IID;
 interface nsIBrowserDOMWindow;
 interface nsIMessageBroadcaster;
-interface nsIDOMCrypto;
 interface XULControllers;
 
 // http://www.whatwg.org/specs/web-apps/current-work/
 [PrimaryGlobal, LegacyUnenumerableNamedProperties, NeedResolve]
 /*sealed*/ interface Window : EventTarget {
   // the current browsing context
   [Unforgeable, Constant, StoreInSlot,
    CrossOriginReadable] readonly attribute Window window;

--- a/dom/workers/WorkerScope.cpp
+++ b/dom/workers/WorkerScope.cpp
@@ -155,18 +155,17 @@ WorkerGlobalScope::GetConsole(ErrorResul
 }
 
 Crypto*
 WorkerGlobalScope::GetCrypto(ErrorResult& aError)
 {
   mWorkerPrivate->AssertIsOnWorkerThread();
 
   if (!mCrypto) {
-    mCrypto = new Crypto();
-    mCrypto->Init(this);
+    mCrypto = new Crypto(this);
   }
 
   return mCrypto;
 }
 
 already_AddRefed<CacheStorage>
 WorkerGlobalScope::GetCaches(ErrorResult& aRv)
 {

--- a/js/xpconnect/src/Sandbox.cpp
+++ b/js/xpconnect/src/Sandbox.cpp
@@ -229,18 +229,17 @@ SandboxImport(JSContext* cx, unsigned ar
 static bool
 SandboxCreateCrypto(JSContext* cx, JS::HandleObject obj)
 {
     MOZ_ASSERT(JS_IsGlobalObject(obj));
 
     nsIGlobalObject* native = xpc::NativeGlobal(obj);
     MOZ_ASSERT(native);
 
-    dom::Crypto* crypto = new dom::Crypto();
-    crypto->Init(native);
+    dom::Crypto* crypto = new dom::Crypto(native);
     JS::RootedObject wrapped(cx, crypto->WrapObject(cx, nullptr));
     return JS_DefineProperty(cx, obj, "crypto", wrapped, JSPROP_ENUMERATE);
 }
 
 #ifdef MOZ_WEBRTC
 static bool
 SandboxCreateRTCIdentityProvider(JSContext* cx, JS::HandleObject obj)
 {