diff --git a/dom/base/Navigator.cpp b/dom/base/Navigator.cpp
index 55e06de7fd08..b3200900ea2b 100644
--- a/dom/base/Navigator.cpp
+++ b/dom/base/Navigator.cpp
@@ -1594,7 +1594,12 @@ void Navigator::GetGamepads(nsTArray<RefPtr<Gamepad>>& aGamepads,
   win->GetGamepads(aGamepads);
 }
 
-GamepadServiceTest* Navigator::RequestGamepadServiceTest() {
+GamepadServiceTest* Navigator::RequestGamepadServiceTest(ErrorResult& aRv) {
+  if (!xpc::IsInAutomation()) {
+    aRv.Throw(NS_ERROR_UNEXPECTED);
+    return nullptr;
+  }
+
   if (!mGamepadServiceTest) {
     mGamepadServiceTest = GamepadServiceTest::CreateTestService(mWindow);
   }
@@ -1759,7 +1764,12 @@ void Navigator::NotifyActiveVRDisplaysChanged() {
   Navigator_Binding::ClearCachedActiveVRDisplaysValue(this);
 }
 
-VRServiceTest* Navigator::RequestVRServiceTest() {
+VRServiceTest* Navigator::RequestVRServiceTest(ErrorResult& aRv) {
+  if (!xpc::IsInAutomation()) {
+    aRv.Throw(NS_ERROR_UNEXPECTED);
+    return nullptr;
+  }
+
   // Ensure that the Mock VR devices are not released prematurely
   nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(mWindow);
   win->NotifyHasXRSession();
diff --git a/dom/base/Navigator.h b/dom/base/Navigator.h
index 0dbb9a5b717a..fd4b1276ab05 100644
--- a/dom/base/Navigator.h
+++ b/dom/base/Navigator.h
@@ -175,13 +175,13 @@ class Navigator final : public nsISupports, public nsWrapperCache {
   MediaDevices* GetExtantMediaDevices() const { return mMediaDevices; };
 
   void GetGamepads(nsTArray<RefPtr<Gamepad>>& aGamepads, ErrorResult& aRv);
-  GamepadServiceTest* RequestGamepadServiceTest();
+  GamepadServiceTest* RequestGamepadServiceTest(ErrorResult& aRv);
   already_AddRefed<Promise> GetVRDisplays(ErrorResult& aRv);
   void FinishGetVRDisplays(bool isWebVRSupportedInwindow, Promise* p);
   void GetActiveVRDisplays(nsTArray<RefPtr<VRDisplay>>& aDisplays) const;
   void OnXRPermissionRequestAllow();
   void OnXRPermissionRequestCancel();
-  VRServiceTest* RequestVRServiceTest();
+  VRServiceTest* RequestVRServiceTest(ErrorResult& aRv);
   bool IsWebVRContentDetected() const;
   bool IsWebVRContentPresenting() const;
   void RequestVRPresentation(VRDisplay& aDisplay);
diff --git a/dom/webidl/Navigator.webidl b/dom/webidl/Navigator.webidl
index 8e2259152f3b..2ceb14716390 100644
--- a/dom/webidl/Navigator.webidl
+++ b/dom/webidl/Navigator.webidl
@@ -209,7 +209,7 @@ partial interface Navigator {
   sequence<Gamepad?> getGamepads();
 };
 partial interface Navigator {
-  [Pref="dom.gamepad.test.enabled"]
+  [Throws, Pref="dom.gamepad.test.enabled"]
   GamepadServiceTest requestGamepadServiceTest();
 };
 
@@ -228,7 +228,7 @@ partial interface Navigator {
   undefined requestVRPresentation(VRDisplay display);
 };
 partial interface Navigator {
-  [Pref="dom.vr.puppet.enabled"]
+  [Throws, Pref="dom.vr.puppet.enabled"]
   VRServiceTest requestVRServiceTest();
 };