Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

74 files changed, 8247 insertions, 0 deletions

diff --git a/dom/vr/VRDisplay.cpp b/dom/vr/VRDisplay.cpp
new file mode 100644
index 0000000000..47e02890af
--- /dev/null
+++ b/dom/vr/VRDisplay.cpp
@@ -0,0 +1,808 @@
+/* -*- 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/. */
+
+#include "nsWrapperCache.h"
+
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/ElementBinding.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/UserActivation.h"
+#include "mozilla/dom/VRDisplay.h"
+#include "mozilla/dom/VRDisplayBinding.h"
+#include "mozilla/HoldDropJSObjects.h"
+#include "mozilla/Base64.h"
+#include "mozilla/ProfilerMarkers.h"
+#include "mozilla/Services.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/gfx/DataSurfaceHelpers.h"
+#include "Navigator.h"
+#include "gfxUtils.h"
+#include "gfxVR.h"
+#include "VRDisplayClient.h"
+#include "VRManagerChild.h"
+#include "VRDisplayPresentation.h"
+#include "nsIObserverService.h"
+#include "nsIFrame.h"
+#include "nsISupportsPrimitives.h"
+
+using namespace mozilla::gfx;
+
+namespace mozilla {
+namespace dom {
+
+VRFieldOfView::VRFieldOfView(nsISupports* aParent, double aUpDegrees,
+                             double aRightDegrees, double aDownDegrees,
+                             double aLeftDegrees)
+    : mParent(aParent),
+      mUpDegrees(aUpDegrees),
+      mRightDegrees(aRightDegrees),
+      mDownDegrees(aDownDegrees),
+      mLeftDegrees(aLeftDegrees) {}
+
+VRFieldOfView::VRFieldOfView(nsISupports* aParent,
+                             const gfx::VRFieldOfView& aSrc)
+    : mParent(aParent),
+      mUpDegrees(aSrc.upDegrees),
+      mRightDegrees(aSrc.rightDegrees),
+      mDownDegrees(aSrc.downDegrees),
+      mLeftDegrees(aSrc.leftDegrees) {}
+
+bool VRDisplayCapabilities::HasPosition() const {
+  return bool(mFlags & gfx::VRDisplayCapabilityFlags::Cap_Position) ||
+         bool(mFlags & gfx::VRDisplayCapabilityFlags::Cap_PositionEmulated);
+}
+
+bool VRDisplayCapabilities::HasOrientation() const {
+  return bool(mFlags & gfx::VRDisplayCapabilityFlags::Cap_Orientation);
+}
+
+bool VRDisplayCapabilities::HasExternalDisplay() const {
+  return bool(mFlags & gfx::VRDisplayCapabilityFlags::Cap_External);
+}
+
+bool VRDisplayCapabilities::CanPresent() const {
+  return bool(mFlags & gfx::VRDisplayCapabilityFlags::Cap_Present);
+}
+
+uint32_t VRDisplayCapabilities::MaxLayers() const {
+  return CanPresent() ? 1 : 0;
+}
+
+void VRDisplay::UpdateDisplayClient(
+    already_AddRefed<gfx::VRDisplayClient> aClient) {
+  mClient = std::move(aClient);
+}
+
+/*static*/
+bool VRDisplay::RefreshVRDisplays(uint64_t aWindowId) {
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  return vm && vm->RefreshVRDisplaysWithCallback(aWindowId);
+}
+
+/*static*/
+void VRDisplay::UpdateVRDisplays(nsTArray<RefPtr<VRDisplay>>& aDisplays,
+                                 nsPIDOMWindowInner* aWindow) {
+  nsTArray<RefPtr<VRDisplay>> displays;
+
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  nsTArray<RefPtr<gfx::VRDisplayClient>> updatedDisplays;
+  if (vm) {
+    vm->GetVRDisplays(updatedDisplays);
+    for (size_t i = 0; i < updatedDisplays.Length(); i++) {
+      RefPtr<gfx::VRDisplayClient> display = updatedDisplays[i];
+      bool isNewDisplay = true;
+      for (size_t j = 0; j < aDisplays.Length(); j++) {
+        if (aDisplays[j]->GetClient()->GetDisplayInfo().GetDisplayID() ==
+            display->GetDisplayInfo().GetDisplayID()) {
+          displays.AppendElement(aDisplays[j]);
+          isNewDisplay = false;
+        } else {
+          RefPtr<gfx::VRDisplayClient> ref = display;
+          aDisplays[j]->UpdateDisplayClient(do_AddRef(display));
+          displays.AppendElement(aDisplays[j]);
+          isNewDisplay = false;
+        }
+      }
+
+      if (isNewDisplay) {
+        displays.AppendElement(new VRDisplay(aWindow, display));
+      }
+    }
+  }
+
+  aDisplays = std::move(displays);
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(VRFieldOfView, mParent)
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(VRFieldOfView, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(VRFieldOfView, Release)
+
+JSObject* VRFieldOfView::WrapObject(JSContext* aCx,
+                                    JS::Handle<JSObject*> aGivenProto) {
+  return VRFieldOfView_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VREyeParameters)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(VREyeParameters)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent, mFOV)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  tmp->mOffset = nullptr;
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(VREyeParameters)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent, mFOV)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(VREyeParameters)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mOffset)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(VREyeParameters, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(VREyeParameters, Release)
+
+VREyeParameters::VREyeParameters(nsISupports* aParent,
+                                 const gfx::Point3D& aEyeTranslation,
+                                 const gfx::VRFieldOfView& aFOV,
+                                 const gfx::IntSize& aRenderSize)
+    : mParent(aParent),
+      mEyeTranslation(aEyeTranslation),
+      mRenderSize(aRenderSize) {
+  mFOV = new VRFieldOfView(aParent, aFOV);
+  mozilla::HoldJSObjects(this);
+}
+
+VREyeParameters::~VREyeParameters() { mozilla::DropJSObjects(this); }
+
+VRFieldOfView* VREyeParameters::FieldOfView() { return mFOV; }
+
+void VREyeParameters::GetOffset(JSContext* aCx,
+                                JS::MutableHandle<JSObject*> aRetval,
+                                ErrorResult& aRv) {
+  if (!mOffset) {
+    // Lazily create the Float32Array
+    mOffset =
+        dom::Float32Array::Create(aCx, this, 3, mEyeTranslation.components);
+    if (!mOffset) {
+      aRv.NoteJSContextException(aCx);
+      return;
+    }
+  }
+  aRetval.set(mOffset);
+}
+
+JSObject* VREyeParameters::WrapObject(JSContext* aCx,
+                                      JS::Handle<JSObject*> aGivenProto) {
+  return VREyeParameters_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+VRStageParameters::VRStageParameters(
+    nsISupports* aParent, const gfx::Matrix4x4& aSittingToStandingTransform,
+    const gfx::Size& aSize)
+    : mParent(aParent),
+      mSittingToStandingTransform(aSittingToStandingTransform),
+      mSittingToStandingTransformArray(nullptr),
+      mSize(aSize) {
+  mozilla::HoldJSObjects(this);
+}
+
+VRStageParameters::~VRStageParameters() { mozilla::DropJSObjects(this); }
+
+JSObject* VRStageParameters::WrapObject(JSContext* aCx,
+                                        JS::Handle<JSObject*> aGivenProto) {
+  return VRStageParameters_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VRStageParameters)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(VRStageParameters)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  tmp->mSittingToStandingTransformArray = nullptr;
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(VRStageParameters)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(VRStageParameters)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(
+      mSittingToStandingTransformArray)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(VRStageParameters, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(VRStageParameters, Release)
+
+void VRStageParameters::GetSittingToStandingTransform(
+    JSContext* aCx, JS::MutableHandle<JSObject*> aRetval, ErrorResult& aRv) {
+  if (!mSittingToStandingTransformArray) {
+    // Lazily create the Float32Array
+    mSittingToStandingTransformArray = dom::Float32Array::Create(
+        aCx, this, 16, mSittingToStandingTransform.components);
+    if (!mSittingToStandingTransformArray) {
+      aRv.NoteJSContextException(aCx);
+      return;
+    }
+  }
+  aRetval.set(mSittingToStandingTransformArray);
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(VRDisplayCapabilities, mParent)
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(VRDisplayCapabilities, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(VRDisplayCapabilities, Release)
+
+JSObject* VRDisplayCapabilities::WrapObject(JSContext* aCx,
+                                            JS::Handle<JSObject*> aGivenProto) {
+  return VRDisplayCapabilities_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+VRPose::VRPose(nsISupports* aParent, const gfx::VRHMDSensorState& aState)
+    : Pose(aParent), mVRState(aState) {
+  mozilla::HoldJSObjects(this);
+}
+
+VRPose::VRPose(nsISupports* aParent) : Pose(aParent) {
+  mVRState.inputFrameID = 0;
+  mVRState.timestamp = 0.0;
+  mVRState.flags = gfx::VRDisplayCapabilityFlags::Cap_None;
+  mozilla::HoldJSObjects(this);
+}
+
+VRPose::~VRPose() { mozilla::DropJSObjects(this); }
+
+void VRPose::GetPosition(JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                         ErrorResult& aRv) {
+  const bool valid =
+      bool(mVRState.flags & gfx::VRDisplayCapabilityFlags::Cap_Position) ||
+      bool(mVRState.flags &
+           gfx::VRDisplayCapabilityFlags::Cap_PositionEmulated);
+  SetFloat32Array(aCx, this, aRetval, mPosition,
+                  valid ? mVRState.pose.position : nullptr, 3, aRv);
+}
+
+void VRPose::GetLinearVelocity(JSContext* aCx,
+                               JS::MutableHandle<JSObject*> aRetval,
+                               ErrorResult& aRv) {
+  const bool valid =
+      bool(mVRState.flags & gfx::VRDisplayCapabilityFlags::Cap_Position) ||
+      bool(mVRState.flags &
+           gfx::VRDisplayCapabilityFlags::Cap_PositionEmulated);
+  SetFloat32Array(aCx, this, aRetval, mLinearVelocity,
+                  valid ? mVRState.pose.linearVelocity : nullptr, 3, aRv);
+}
+
+void VRPose::GetLinearAcceleration(JSContext* aCx,
+                                   JS::MutableHandle<JSObject*> aRetval,
+                                   ErrorResult& aRv) {
+  const bool valid = bool(
+      mVRState.flags & gfx::VRDisplayCapabilityFlags::Cap_LinearAcceleration);
+  SetFloat32Array(aCx, this, aRetval, mLinearAcceleration,
+                  valid ? mVRState.pose.linearAcceleration : nullptr, 3, aRv);
+}
+
+void VRPose::GetOrientation(JSContext* aCx,
+                            JS::MutableHandle<JSObject*> aRetval,
+                            ErrorResult& aRv) {
+  const bool valid =
+      bool(mVRState.flags & gfx::VRDisplayCapabilityFlags::Cap_Orientation);
+  SetFloat32Array(aCx, this, aRetval, mOrientation,
+                  valid ? mVRState.pose.orientation : nullptr, 4, aRv);
+}
+
+void VRPose::GetAngularVelocity(JSContext* aCx,
+                                JS::MutableHandle<JSObject*> aRetval,
+                                ErrorResult& aRv) {
+  const bool valid =
+      bool(mVRState.flags & gfx::VRDisplayCapabilityFlags::Cap_Orientation);
+  SetFloat32Array(aCx, this, aRetval, mAngularVelocity,
+                  valid ? mVRState.pose.angularVelocity : nullptr, 3, aRv);
+}
+
+void VRPose::GetAngularAcceleration(JSContext* aCx,
+                                    JS::MutableHandle<JSObject*> aRetval,
+                                    ErrorResult& aRv) {
+  const bool valid = bool(
+      mVRState.flags & gfx::VRDisplayCapabilityFlags::Cap_AngularAcceleration);
+  SetFloat32Array(aCx, this, aRetval, mAngularAcceleration,
+                  valid ? mVRState.pose.angularAcceleration : nullptr, 3, aRv);
+}
+
+void VRPose::Update(const gfx::VRHMDSensorState& aState) { mVRState = aState; }
+
+JSObject* VRPose::WrapObject(JSContext* aCx,
+                             JS::Handle<JSObject*> aGivenProto) {
+  return VRPose_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+/* virtual */
+JSObject* VRDisplay::WrapObject(JSContext* aCx,
+                                JS::Handle<JSObject*> aGivenProto) {
+  return VRDisplay_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+VRDisplay::VRDisplay(nsPIDOMWindowInner* aWindow, gfx::VRDisplayClient* aClient)
+    : DOMEventTargetHelper(aWindow),
+      mClient(aClient),
+      mDepthNear(0.01f)  // Default value from WebVR Spec
+      ,
+      mDepthFar(10000.0f)  // Default value from WebVR Spec
+      ,
+      mVRNavigationEventDepth(0),
+      mShutdown(false) {
+  const gfx::VRDisplayInfo& info = aClient->GetDisplayInfo();
+  mCapabilities = new VRDisplayCapabilities(aWindow, info.GetCapabilities());
+  if (info.GetCapabilities() &
+      gfx::VRDisplayCapabilityFlags::Cap_StageParameters) {
+    mStageParameters = new VRStageParameters(
+        aWindow, info.GetSittingToStandingTransform(), info.GetStageSize());
+  }
+  mozilla::HoldJSObjects(this);
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+  if (MOZ_LIKELY(obs)) {
+    obs->AddObserver(this, "inner-window-destroyed", false);
+  }
+}
+
+VRDisplay::~VRDisplay() {
+  MOZ_ASSERT(mShutdown);
+  mozilla::DropJSObjects(this);
+}
+
+void VRDisplay::LastRelease() {
+  // We don't want to wait for the CC to free up the presentation
+  // for use in other documents, so we do this in LastRelease().
+  Shutdown();
+}
+
+already_AddRefed<VREyeParameters> VRDisplay::GetEyeParameters(VREye aEye) {
+  gfx::VRDisplayState::Eye eye = aEye == VREye::Left
+                                     ? gfx::VRDisplayState::Eye_Left
+                                     : gfx::VRDisplayState::Eye_Right;
+  RefPtr<VREyeParameters> params = new VREyeParameters(
+      GetParentObject(), mClient->GetDisplayInfo().GetEyeTranslation(eye),
+      mClient->GetDisplayInfo().GetEyeFOV(eye),
+      mClient->GetDisplayInfo().SuggestedEyeResolution());
+  return params.forget();
+}
+
+VRDisplayCapabilities* VRDisplay::Capabilities() { return mCapabilities; }
+
+VRStageParameters* VRDisplay::GetStageParameters() { return mStageParameters; }
+
+uint32_t VRDisplay::DisplayId() const {
+  const gfx::VRDisplayInfo& info = mClient->GetDisplayInfo();
+  return info.GetDisplayID();
+}
+
+void VRDisplay::GetDisplayName(nsAString& aDisplayName) const {
+  const gfx::VRDisplayInfo& info = mClient->GetDisplayInfo();
+  CopyUTF8toUTF16(MakeStringSpan(info.GetDisplayName()), aDisplayName);
+}
+
+void VRDisplay::UpdateFrameInfo() {
+  /**
+   * The WebVR 1.1 spec Requires that VRDisplay.getPose and
+   * VRDisplay.getFrameData must return the same values until the next
+   * VRDisplay.submitFrame.
+   *
+   * mFrameInfo is marked dirty at the end of the frame or start of a new
+   * composition and lazily created here in order to receive mid-frame
+   * pose-prediction updates while still ensuring conformance to the WebVR spec
+   * requirements.
+   *
+   * If we are not presenting WebVR content, the frame will never end and we
+   * should return the latest frame data always.
+   */
+  mFrameInfo.Clear();
+
+  if ((mFrameInfo.IsDirty() && IsPresenting()) ||
+      mClient->GetDisplayInfo().GetPresentingGroups() == 0) {
+    const gfx::VRHMDSensorState& state = mClient->GetSensorState();
+    const gfx::VRDisplayInfo& info = mClient->GetDisplayInfo();
+    mFrameInfo.Update(info, state, mDepthNear, mDepthFar);
+  }
+}
+
+bool VRDisplay::GetFrameData(VRFrameData& aFrameData) {
+  UpdateFrameInfo();
+  if (!(mFrameInfo.mVRState.flags &
+        gfx::VRDisplayCapabilityFlags::Cap_Orientation)) {
+    // We must have at minimum Cap_Orientation for a valid pose.
+    return false;
+  }
+  aFrameData.Update(mFrameInfo);
+  return true;
+}
+
+already_AddRefed<VRPose> VRDisplay::GetPose() {
+  UpdateFrameInfo();
+  RefPtr<VRPose> obj = new VRPose(GetParentObject(), mFrameInfo.mVRState);
+
+  return obj.forget();
+}
+
+void VRDisplay::ResetPose() {
+  // ResetPose is deprecated and unimplemented
+  // We must keep this stub function around as its referenced by
+  // VRDisplay.webidl. Not asserting here, as that could break existing web
+  // content.
+}
+
+void VRDisplay::StartVRNavigation() { mClient->StartVRNavigation(); }
+
+void VRDisplay::StartHandlingVRNavigationEvent() {
+  mHandlingVRNavigationEventStart = TimeStamp::Now();
+  ++mVRNavigationEventDepth;
+  TimeDuration timeout =
+      TimeDuration::FromMilliseconds(StaticPrefs::dom_vr_navigation_timeout());
+  // A 0 or negative TimeDuration indicates that content may take
+  // as long as it wishes to respond to the event, as long as
+  // it happens before the event exits.
+  if (timeout.ToMilliseconds() > 0) {
+    mClient->StopVRNavigation(timeout);
+  }
+}
+
+void VRDisplay::StopHandlingVRNavigationEvent() {
+  MOZ_ASSERT(mVRNavigationEventDepth > 0);
+  --mVRNavigationEventDepth;
+  if (mVRNavigationEventDepth == 0) {
+    mClient->StopVRNavigation(TimeDuration::FromMilliseconds(0));
+  }
+}
+
+bool VRDisplay::IsHandlingVRNavigationEvent() {
+  if (mVRNavigationEventDepth == 0) {
+    return false;
+  }
+  if (mHandlingVRNavigationEventStart.IsNull()) {
+    return false;
+  }
+  TimeDuration timeout =
+      TimeDuration::FromMilliseconds(StaticPrefs::dom_vr_navigation_timeout());
+  return timeout.ToMilliseconds() <= 0 ||
+         (TimeStamp::Now() - mHandlingVRNavigationEventStart) <= timeout;
+}
+
+void VRDisplay::OnPresentationGenerationChanged() { ExitPresentInternal(); }
+
+already_AddRefed<Promise> VRDisplay::RequestPresent(
+    const nsTArray<VRLayer>& aLayers, CallerType aCallerType,
+    ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  if (!global) {
+    aRv.Throw(NS_ERROR_FAILURE);
+    return nullptr;
+  }
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  bool isChromePresentation = aCallerType == CallerType::System;
+  uint32_t presentationGroup =
+      isChromePresentation ? gfx::kVRGroupChrome : gfx::kVRGroupContent;
+
+  mClient->SetXRAPIMode(gfx::VRAPIMode::WebVR);
+  if (!UserActivation::IsHandlingUserInput() && !isChromePresentation &&
+      !IsHandlingVRNavigationEvent() && StaticPrefs::dom_vr_require_gesture() &&
+      !IsPresenting()) {
+    // The WebVR API states that if called outside of a user gesture, the
+    // promise must be rejected.  We allow VR presentations to start within
+    // trusted events such as vrdisplayactivate, which triggers in response to
+    // HMD proximity sensors and when navigating within a VR presentation.
+    // This user gesture requirement is not enforced for chrome/system code.
+    promise->MaybeRejectWithUndefined();
+  } else if (!IsPresenting() && IsAnyPresenting(presentationGroup)) {
+    // Only one presentation allowed per VRDisplay on a
+    // first-come-first-serve basis.
+    // If this Javascript context is presenting, then we can replace our
+    // presentation with a new one containing new layers but we should never
+    // replace the presentation of another context.
+    // Simultaneous presentations in other groups are allowed in separate
+    // Javascript contexts to enable browser UI from chrome/system contexts.
+    // Eventually, this restriction will be loosened to enable multitasking
+    // use cases.
+    promise->MaybeRejectWithUndefined();
+  } else {
+    if (mPresentation) {
+      mPresentation->UpdateLayers(aLayers);
+    } else {
+      mPresentation = mClient->BeginPresentation(aLayers, presentationGroup);
+    }
+    mFrameInfo.Clear();
+    promise->MaybeResolve(JS::UndefinedHandleValue);
+  }
+  return promise.forget();
+}
+
+NS_IMETHODIMP
+VRDisplay::Observe(nsISupports* aSubject, const char* aTopic,
+                   const char16_t* aData) {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (strcmp(aTopic, "inner-window-destroyed") == 0) {
+    nsCOMPtr<nsISupportsPRUint64> wrapper = do_QueryInterface(aSubject);
+    NS_ENSURE_TRUE(wrapper, NS_ERROR_FAILURE);
+
+    uint64_t innerID;
+    nsresult rv = wrapper->GetData(&innerID);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!GetOwner() || GetOwner()->WindowID() == innerID) {
+      Shutdown();
+    }
+
+    return NS_OK;
+  }
+
+  // This should not happen.
+  return NS_ERROR_FAILURE;
+}
+
+already_AddRefed<Promise> VRDisplay::ExitPresent(ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  if (!global) {
+    aRv.Throw(NS_ERROR_FAILURE);
+    return nullptr;
+  }
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  if (!IsPresenting()) {
+    // We can not exit a presentation outside of the context that
+    // started the presentation.
+    promise->MaybeRejectWithUndefined();
+  } else {
+    promise->MaybeResolve(JS::UndefinedHandleValue);
+    ExitPresentInternal();
+  }
+
+  return promise.forget();
+}
+
+void VRDisplay::ExitPresentInternal() { mPresentation = nullptr; }
+
+void VRDisplay::Shutdown() {
+  mShutdown = true;
+  ExitPresentInternal();
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+  if (MOZ_LIKELY(obs)) {
+    obs->RemoveObserver(this, "inner-window-destroyed");
+  }
+}
+
+void VRDisplay::GetLayers(nsTArray<VRLayer>& result) {
+  if (mPresentation) {
+    mPresentation->GetDOMLayers(result);
+  } else {
+    result = nsTArray<VRLayer>();
+  }
+}
+
+void VRDisplay::SubmitFrame() {
+  AUTO_PROFILER_TRACING_MARKER("VR", "SubmitFrameAtVRDisplay", OTHER);
+
+  if (mClient && !mClient->IsPresentationGenerationCurrent()) {
+    mPresentation = nullptr;
+    mClient->MakePresentationGenerationCurrent();
+  }
+
+  if (mPresentation) {
+    mPresentation->SubmitFrame();
+  }
+  mFrameInfo.Clear();
+}
+
+int32_t VRDisplay::RequestAnimationFrame(FrameRequestCallback& aCallback,
+                                         ErrorResult& aError) {
+  if (mShutdown) {
+    return 0;
+  }
+
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+
+  int32_t handle;
+  aError = vm->ScheduleFrameRequestCallback(aCallback, &handle);
+  return handle;
+}
+
+void VRDisplay::CancelAnimationFrame(int32_t aHandle, ErrorResult& aError) {
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  vm->CancelFrameRequestCallback(aHandle);
+}
+
+bool VRDisplay::IsPresenting() const {
+  // IsPresenting returns true only if this Javascript context is presenting
+  // and will return false if another context is presenting.
+  return mPresentation != nullptr;
+}
+
+bool VRDisplay::IsAnyPresenting(uint32_t aGroupMask) const {
+  // IsAnyPresenting returns true if either this VRDisplay object or any other
+  // from anther Javascript context is presenting with a group matching
+  // aGroupMask.
+  if (mPresentation && (mPresentation->GetGroup() & aGroupMask)) {
+    return true;
+  }
+  if (mClient->GetDisplayInfo().GetPresentingGroups() & aGroupMask) {
+    return true;
+  }
+  return false;
+}
+
+bool VRDisplay::IsConnected() const { return mClient->GetIsConnected(); }
+
+uint32_t VRDisplay::PresentingGroups() const {
+  return mClient->GetDisplayInfo().GetPresentingGroups();
+}
+
+uint32_t VRDisplay::GroupMask() const {
+  return mClient->GetDisplayInfo().GetGroupMask();
+}
+
+void VRDisplay::SetGroupMask(const uint32_t& aGroupMask) {
+  mClient->SetGroupMask(aGroupMask);
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(VRDisplay, DOMEventTargetHelper,
+                                   mCapabilities, mStageParameters)
+
+NS_IMPL_ADDREF_INHERITED(VRDisplay, DOMEventTargetHelper)
+NS_IMPL_RELEASE_INHERITED(VRDisplay, DOMEventTargetHelper)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(VRDisplay)
+  NS_INTERFACE_MAP_ENTRY(nsIObserver)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, DOMEventTargetHelper)
+NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VRFrameData)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(VRFrameData)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent, mPose)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  tmp->mLeftProjectionMatrix = nullptr;
+  tmp->mLeftViewMatrix = nullptr;
+  tmp->mRightProjectionMatrix = nullptr;
+  tmp->mRightViewMatrix = nullptr;
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(VRFrameData)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent, mPose)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(VRFrameData)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mLeftProjectionMatrix)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mLeftViewMatrix)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mRightProjectionMatrix)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mRightViewMatrix)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(VRFrameData, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(VRFrameData, Release)
+
+VRFrameData::VRFrameData(nsISupports* aParent)
+    : mParent(aParent),
+      mLeftProjectionMatrix(nullptr),
+      mLeftViewMatrix(nullptr),
+      mRightProjectionMatrix(nullptr),
+      mRightViewMatrix(nullptr) {
+  mozilla::HoldJSObjects(this);
+  mPose = new VRPose(aParent);
+}
+
+VRFrameData::~VRFrameData() { mozilla::DropJSObjects(this); }
+
+/* static */
+already_AddRefed<VRFrameData> VRFrameData::Constructor(
+    const GlobalObject& aGlobal) {
+  RefPtr<VRFrameData> obj = new VRFrameData(aGlobal.GetAsSupports());
+  return obj.forget();
+}
+
+JSObject* VRFrameData::WrapObject(JSContext* aCx,
+                                  JS::Handle<JSObject*> aGivenProto) {
+  return VRFrameData_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+VRPose* VRFrameData::Pose() { return mPose; }
+
+double VRFrameData::Timestamp() const {
+  // Converting from seconds to milliseconds
+  return mFrameInfo.mVRState.timestamp * 1000.0f;
+}
+
+void VRFrameData::GetLeftProjectionMatrix(JSContext* aCx,
+                                          JS::MutableHandle<JSObject*> aRetval,
+                                          ErrorResult& aRv) {
+  Pose::SetFloat32Array(aCx, this, aRetval, mLeftProjectionMatrix,
+                        mFrameInfo.mLeftProjection.components, 16, aRv);
+}
+
+void VRFrameData::GetLeftViewMatrix(JSContext* aCx,
+                                    JS::MutableHandle<JSObject*> aRetval,
+                                    ErrorResult& aRv) {
+  Pose::SetFloat32Array(aCx, this, aRetval, mLeftViewMatrix,
+                        mFrameInfo.mLeftView.components, 16, aRv);
+}
+
+void VRFrameData::GetRightProjectionMatrix(JSContext* aCx,
+                                           JS::MutableHandle<JSObject*> aRetval,
+                                           ErrorResult& aRv) {
+  Pose::SetFloat32Array(aCx, this, aRetval, mRightProjectionMatrix,
+                        mFrameInfo.mRightProjection.components, 16, aRv);
+}
+
+void VRFrameData::GetRightViewMatrix(JSContext* aCx,
+                                     JS::MutableHandle<JSObject*> aRetval,
+                                     ErrorResult& aRv) {
+  Pose::SetFloat32Array(aCx, this, aRetval, mRightViewMatrix,
+                        mFrameInfo.mRightView.components, 16, aRv);
+}
+
+void VRFrameData::Update(const VRFrameInfo& aFrameInfo) {
+  mFrameInfo = aFrameInfo;
+  mPose->Update(mFrameInfo.mVRState);
+}
+
+void VRFrameInfo::Update(const gfx::VRDisplayInfo& aInfo,
+                         const gfx::VRHMDSensorState& aState, float aDepthNear,
+                         float aDepthFar) {
+  mVRState = aState;
+  if (mTimeStampOffset == 0.0f) {
+    /**
+     * A mTimeStampOffset value of 0.0f indicates that this is the first
+     * iteration and an offset has not yet been set.
+     *
+     * Generate a value for mTimeStampOffset such that if aState.timestamp is
+     * monotonically increasing, aState.timestamp + mTimeStampOffset will never
+     * be a negative number and will start at a pseudo-random offset
+     * between 1000.0f and 11000.0f seconds.
+     *
+     * We use a pseudo random offset rather than 0.0f just to discourage users
+     * from making the assumption that the timestamp returned in the WebVR API
+     * has a base of 0, which is not necessarily true in all UA's.
+     */
+    mTimeStampOffset =
+        float(rand()) / float(RAND_MAX) * 10000.0f + 1000.0f - aState.timestamp;
+  }
+  mVRState.timestamp = aState.timestamp + mTimeStampOffset;
+
+  // Avoid division by zero within ConstructProjectionMatrix
+  const float kEpsilon = 0.00001f;
+  if (fabs(aDepthFar - aDepthNear) < kEpsilon) {
+    aDepthFar = aDepthNear + kEpsilon;
+  }
+
+  const gfx::VRFieldOfView leftFOV =
+      aInfo.mDisplayState.eyeFOV[gfx::VRDisplayState::Eye_Left];
+  mLeftProjection =
+      leftFOV.ConstructProjectionMatrix(aDepthNear, aDepthFar, true);
+  const gfx::VRFieldOfView rightFOV =
+      aInfo.mDisplayState.eyeFOV[gfx::VRDisplayState::Eye_Right];
+  mRightProjection =
+      rightFOV.ConstructProjectionMatrix(aDepthNear, aDepthFar, true);
+  memcpy(mLeftView.components, aState.leftViewMatrix,
+         sizeof(aState.leftViewMatrix));
+  memcpy(mRightView.components, aState.rightViewMatrix,
+         sizeof(aState.rightViewMatrix));
+}
+
+VRFrameInfo::VRFrameInfo() : mTimeStampOffset(0.0f) {
+  mVRState.inputFrameID = 0;
+  mVRState.timestamp = 0.0;
+  mVRState.flags = gfx::VRDisplayCapabilityFlags::Cap_None;
+}
+
+bool VRFrameInfo::IsDirty() { return mVRState.timestamp == 0; }
+
+void VRFrameInfo::Clear() { mVRState.Clear(); }
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/VRDisplay.h b/dom/vr/VRDisplay.h
new file mode 100644
index 0000000000..1f4de0ee0c
--- /dev/null
+++ b/dom/vr/VRDisplay.h
@@ -0,0 +1,367 @@
+/* -*- 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_VRDisplay_h_
+#define mozilla_dom_VRDisplay_h_
+
+#include <stdint.h>
+
+#include "mozilla/dom/TypedArray.h"
+#include "mozilla/dom/VRDisplayBinding.h"
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/DOMPoint.h"
+#include "mozilla/dom/DOMRect.h"
+#include "mozilla/dom/Pose.h"
+#include "mozilla/TimeStamp.h"
+
+#include "nsCOMPtr.h"
+#include "nsString.h"
+#include "nsTArray.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+class ErrorResult;
+
+namespace gfx {
+class VRDisplayClient;
+class VRDisplayPresentation;
+struct VRFieldOfView;
+enum class VRDisplayCapabilityFlags : uint16_t;
+struct VRHMDSensorState;
+}  // namespace gfx
+namespace dom {
+class Navigator;
+
+class VRFieldOfView final : public nsWrapperCache {
+ public:
+  VRFieldOfView(nsISupports* aParent, double aUpDegrees, double aRightDegrees,
+                double aDownDegrees, double aLeftDegrees);
+  VRFieldOfView(nsISupports* aParent, const gfx::VRFieldOfView& aSrc);
+
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(VRFieldOfView)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(VRFieldOfView)
+
+  double UpDegrees() const { return mUpDegrees; }
+  double RightDegrees() const { return mRightDegrees; }
+  double DownDegrees() const { return mDownDegrees; }
+  double LeftDegrees() const { return mLeftDegrees; }
+
+  nsISupports* GetParentObject() const { return mParent; }
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+ protected:
+  virtual ~VRFieldOfView() = default;
+
+  nsCOMPtr<nsISupports> mParent;
+
+  double mUpDegrees;
+  double mRightDegrees;
+  double mDownDegrees;
+  double mLeftDegrees;
+};
+
+class VRDisplayCapabilities final : public nsWrapperCache {
+ public:
+  VRDisplayCapabilities(nsISupports* aParent,
+                        const gfx::VRDisplayCapabilityFlags& aFlags)
+      : mParent(aParent), mFlags(aFlags) {}
+
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(VRDisplayCapabilities)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(VRDisplayCapabilities)
+
+  nsISupports* GetParentObject() const { return mParent; }
+
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+  bool HasPosition() const;
+  bool HasOrientation() const;
+  bool HasExternalDisplay() const;
+  bool CanPresent() const;
+  uint32_t MaxLayers() const;
+
+ protected:
+  ~VRDisplayCapabilities() = default;
+  nsCOMPtr<nsISupports> mParent;
+  gfx::VRDisplayCapabilityFlags mFlags;
+};
+
+class VRPose final : public Pose {
+ public:
+  VRPose(nsISupports* aParent, const gfx::VRHMDSensorState& aState);
+  explicit VRPose(nsISupports* aParent);
+
+  virtual void GetPosition(JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                           ErrorResult& aRv) override;
+  virtual void GetLinearVelocity(JSContext* aCx,
+                                 JS::MutableHandle<JSObject*> aRetval,
+                                 ErrorResult& aRv) override;
+  virtual void GetLinearAcceleration(JSContext* aCx,
+                                     JS::MutableHandle<JSObject*> aRetval,
+                                     ErrorResult& aRv) override;
+  virtual void GetOrientation(JSContext* aCx,
+                              JS::MutableHandle<JSObject*> aRetval,
+                              ErrorResult& aRv) override;
+  virtual void GetAngularVelocity(JSContext* aCx,
+                                  JS::MutableHandle<JSObject*> aRetval,
+                                  ErrorResult& aRv) override;
+  virtual void GetAngularAcceleration(JSContext* aCx,
+                                      JS::MutableHandle<JSObject*> aRetval,
+                                      ErrorResult& aRv) override;
+
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+  void Update(const gfx::VRHMDSensorState& aState);
+
+ protected:
+  ~VRPose();
+
+  gfx::VRHMDSensorState mVRState;
+};
+
+struct VRFrameInfo {
+  VRFrameInfo();
+
+  void Update(const gfx::VRDisplayInfo& aInfo,
+              const gfx::VRHMDSensorState& aState, float aDepthNear,
+              float aDepthFar);
+
+  void Clear();
+  bool IsDirty();
+
+  gfx::VRHMDSensorState mVRState;
+  gfx::Matrix4x4 mLeftProjection;
+  gfx::Matrix4x4 mLeftView;
+  gfx::Matrix4x4 mRightProjection;
+  gfx::Matrix4x4 mRightView;
+
+  /**
+   * In order to avoid leaking information related to the duration of
+   * the user's VR session, we re-base timestamps.
+   * mTimeStampOffset is added to the actual timestamp returned by the
+   * underlying VR platform API when returned through WebVR API's.
+   */
+  double mTimeStampOffset;
+};
+
+class VRFrameData final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(VRFrameData)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(VRFrameData)
+
+  explicit VRFrameData(nsISupports* aParent);
+  static already_AddRefed<VRFrameData> Constructor(const GlobalObject& aGlobal);
+
+  void Update(const VRFrameInfo& aFrameInfo);
+
+  // WebIDL Members
+  double Timestamp() const;
+  void GetLeftProjectionMatrix(JSContext* aCx,
+                               JS::MutableHandle<JSObject*> aRetval,
+                               ErrorResult& aRv);
+  void GetLeftViewMatrix(JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                         ErrorResult& aRv);
+  void GetRightProjectionMatrix(JSContext* aCx,
+                                JS::MutableHandle<JSObject*> aRetval,
+                                ErrorResult& aRv);
+  void GetRightViewMatrix(JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                          ErrorResult& aRv);
+
+  VRPose* Pose();
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+ protected:
+  ~VRFrameData();
+  nsCOMPtr<nsISupports> mParent;
+
+  VRFrameInfo mFrameInfo;
+  RefPtr<VRPose> mPose;
+  JS::Heap<JSObject*> mLeftProjectionMatrix;
+  JS::Heap<JSObject*> mLeftViewMatrix;
+  JS::Heap<JSObject*> mRightProjectionMatrix;
+  JS::Heap<JSObject*> mRightViewMatrix;
+
+  void LazyCreateMatrix(JS::Heap<JSObject*>& aArray, gfx::Matrix4x4& aMat,
+                        JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                        ErrorResult& aRv);
+};
+
+class VRStageParameters final : public nsWrapperCache {
+ public:
+  VRStageParameters(nsISupports* aParent,
+                    const gfx::Matrix4x4& aSittingToStandingTransform,
+                    const gfx::Size& aSize);
+
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(VRStageParameters)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(VRStageParameters)
+
+  void GetSittingToStandingTransform(JSContext* aCx,
+                                     JS::MutableHandle<JSObject*> aRetval,
+                                     ErrorResult& aRv);
+  float SizeX() const { return mSize.width; }
+  float SizeZ() const { return mSize.height; }
+
+  nsISupports* GetParentObject() const { return mParent; }
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+ protected:
+  ~VRStageParameters();
+
+  nsCOMPtr<nsISupports> mParent;
+
+  gfx::Matrix4x4 mSittingToStandingTransform;
+  JS::Heap<JSObject*> mSittingToStandingTransformArray;
+  gfx::Size mSize;
+};
+
+class VREyeParameters final : public nsWrapperCache {
+ public:
+  VREyeParameters(nsISupports* aParent, const gfx::Point3D& aEyeTranslation,
+                  const gfx::VRFieldOfView& aFOV,
+                  const gfx::IntSize& aRenderSize);
+
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(VREyeParameters)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(VREyeParameters)
+
+  void GetOffset(JSContext* aCx, JS::MutableHandle<JSObject*> aRetVal,
+                 ErrorResult& aRv);
+
+  VRFieldOfView* FieldOfView();
+
+  uint32_t RenderWidth() const { return mRenderSize.width; }
+  uint32_t RenderHeight() const { return mRenderSize.height; }
+
+  nsISupports* GetParentObject() const { return mParent; }
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+ protected:
+  ~VREyeParameters();
+
+  nsCOMPtr<nsISupports> mParent;
+
+  gfx::Point3D mEyeTranslation;
+  gfx::IntSize mRenderSize;
+  JS::Heap<JSObject*> mOffset;
+  RefPtr<VRFieldOfView> mFOV;
+};
+
+class VRDisplay final : public DOMEventTargetHelper, public nsIObserver {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSIOBSERVER
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(VRDisplay, DOMEventTargetHelper)
+
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+  uint32_t PresentingGroups() const;
+  uint32_t GroupMask() const;
+  void SetGroupMask(const uint32_t& aGroupMask);
+  bool IsAnyPresenting(uint32_t aGroupMask) const;
+  bool IsPresenting() const;
+  bool IsConnected() const;
+
+  VRDisplayCapabilities* Capabilities();
+  VRStageParameters* GetStageParameters();
+
+  uint32_t DisplayId() const;
+  void GetDisplayName(nsAString& aDisplayName) const;
+  // Replacing the old VRDisplayClient with the newest one to avoid
+  // JS needs to reload to recover VRDisplay when VRService is shutdown at the
+  // backend.
+  void UpdateDisplayClient(already_AddRefed<gfx::VRDisplayClient> aClient);
+
+  static bool RefreshVRDisplays(uint64_t aWindowId);
+  static void UpdateVRDisplays(nsTArray<RefPtr<VRDisplay> >& aDisplays,
+                               nsPIDOMWindowInner* aWindow);
+
+  gfx::VRDisplayClient* GetClient() { return mClient; }
+
+  virtual already_AddRefed<VREyeParameters> GetEyeParameters(VREye aEye);
+
+  bool GetFrameData(VRFrameData& aFrameData);
+  already_AddRefed<VRPose> GetPose();
+  void ResetPose();
+
+  double DepthNear() { return mDepthNear; }
+
+  double DepthFar() { return mDepthFar; }
+
+  void SetDepthNear(double aDepthNear) {
+    // XXX When we start sending depth buffers to VRLayer's we will want
+    // to communicate this with the VRDisplayHost
+    mDepthNear = aDepthNear;
+  }
+
+  void SetDepthFar(double aDepthFar) {
+    // XXX When we start sending depth buffers to VRLayer's we will want
+    // to communicate this with the VRDisplayHost
+    mDepthFar = aDepthFar;
+  }
+
+  already_AddRefed<Promise> RequestPresent(const nsTArray<VRLayer>& aLayers,
+                                           CallerType aCallerType,
+                                           ErrorResult& aRv);
+  already_AddRefed<Promise> ExitPresent(ErrorResult& aRv);
+  void GetLayers(nsTArray<VRLayer>& result);
+  void SubmitFrame();
+
+  int32_t RequestAnimationFrame(mozilla::dom::FrameRequestCallback& aCallback,
+                                mozilla::ErrorResult& aError);
+  void CancelAnimationFrame(int32_t aHandle, mozilla::ErrorResult& aError);
+  void StartVRNavigation();
+  void StartHandlingVRNavigationEvent();
+  void StopHandlingVRNavigationEvent();
+  bool IsHandlingVRNavigationEvent();
+  void OnPresentationGenerationChanged();
+
+ protected:
+  VRDisplay(nsPIDOMWindowInner* aWindow, gfx::VRDisplayClient* aClient);
+  virtual ~VRDisplay();
+  virtual void LastRelease() override;
+
+  void ExitPresentInternal();
+  void Shutdown();
+  void UpdateFrameInfo();
+
+  RefPtr<gfx::VRDisplayClient> mClient;
+
+  RefPtr<VRDisplayCapabilities> mCapabilities;
+  RefPtr<VRStageParameters> mStageParameters;
+
+  double mDepthNear;
+  double mDepthFar;
+
+  RefPtr<gfx::VRDisplayPresentation> mPresentation;
+
+  /**
+   * The WebVR 1.1 spec Requires that VRDisplay.getPose and
+   * VRDisplay.getFrameData must return the same values until the next
+   * VRDisplay.submitFrame. mFrameInfo is updated only on the first call to
+   * either function within one frame.  Subsequent calls before the next
+   * SubmitFrame or ExitPresent call will use these cached values.
+   */
+  VRFrameInfo mFrameInfo;
+
+  // Time at which we began expecting VR navigation.
+  TimeStamp mHandlingVRNavigationEventStart;
+  int32_t mVRNavigationEventDepth;
+  bool mShutdown;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif
diff --git a/dom/vr/VRDisplayEvent.cpp b/dom/vr/VRDisplayEvent.cpp
new file mode 100644
index 0000000000..42c9f4b38a
--- /dev/null
+++ b/dom/vr/VRDisplayEvent.cpp
@@ -0,0 +1,76 @@
+/* -*- 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/. */
+
+#include "VRDisplayEvent.h"
+#include "js/RootingAPI.h"
+#include "mozilla/dom/Nullable.h"
+#include "mozilla/dom/PrimitiveConversions.h"
+
+using namespace mozilla::gfx;
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VRDisplayEvent)
+
+NS_IMPL_ADDREF_INHERITED(VRDisplayEvent, Event)
+NS_IMPL_RELEASE_INHERITED(VRDisplayEvent, Event)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(VRDisplayEvent, Event)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN_INHERITED(VRDisplayEvent, Event)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(VRDisplayEvent, Event)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(VRDisplayEvent)
+NS_INTERFACE_MAP_END_INHERITING(Event)
+
+VRDisplayEvent::VRDisplayEvent(mozilla::dom::EventTarget* aOwner)
+    : Event(aOwner, nullptr, nullptr) {}
+
+VRDisplay* VRDisplayEvent::Display() { return mDisplay; }
+
+JSObject* VRDisplayEvent::WrapObjectInternal(
+    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
+  return VRDisplayEvent_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+already_AddRefed<VRDisplayEvent> VRDisplayEvent::Constructor(
+    mozilla::dom::EventTarget* aOwner, const nsAString& aType,
+    const VRDisplayEventInit& aEventInitDict) {
+  RefPtr<VRDisplayEvent> e = new VRDisplayEvent(aOwner);
+  bool trusted = e->Init(aOwner);
+  e->InitEvent(aType, aEventInitDict.mBubbles, aEventInitDict.mCancelable);
+  if (aEventInitDict.mReason.WasPassed()) {
+    e->mReason = Some(aEventInitDict.mReason.Value());
+  }
+  e->mDisplay = aEventInitDict.mDisplay;
+  e->SetTrusted(trusted);
+  e->SetComposed(aEventInitDict.mComposed);
+  return e.forget();
+}
+
+already_AddRefed<VRDisplayEvent> VRDisplayEvent::Constructor(
+    const GlobalObject& aGlobal, const nsAString& aType,
+    const VRDisplayEventInit& aEventInitDict) {
+  nsCOMPtr<mozilla::dom::EventTarget> owner =
+      do_QueryInterface(aGlobal.GetAsSupports());
+  return Constructor(owner, aType, aEventInitDict);
+}
+
+Nullable<VRDisplayEventReason> VRDisplayEvent::GetReason() const {
+  if (mReason.isSome()) {
+    return mReason.value();
+  }
+
+  return nullptr;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/VRDisplayEvent.h b/dom/vr/VRDisplayEvent.h
new file mode 100644
index 0000000000..3439833b66
--- /dev/null
+++ b/dom/vr/VRDisplayEvent.h
@@ -0,0 +1,65 @@
+/* -*- 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_VRDisplayEvent_h_
+#define mozilla_dom_VRDisplayEvent_h_
+
+#include "js/RootingAPI.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/dom/Event.h"
+#include "mozilla/dom/Nullable.h"
+#include "mozilla/dom/VRDisplay.h"
+#include "mozilla/dom/VRDisplayEventBinding.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsISupports.h"
+#include "nsStringFwd.h"
+
+struct JSContext;
+
+namespace mozilla {
+namespace gfx {
+class VRDisplay;
+}  // namespace gfx
+
+namespace dom {
+
+class VRDisplayEvent final : public Event {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(VRDisplayEvent, Event)
+
+  VRDisplay* Display();
+  Nullable<VRDisplayEventReason> GetReason() const;
+
+ protected:
+  virtual ~VRDisplayEvent() = default;
+  explicit VRDisplayEvent(mozilla::dom::EventTarget* aOwner);
+  VRDisplayEvent(EventTarget* aOwner, nsPresContext* aPresContext,
+                 InternalClipboardEvent* aEvent);
+
+  Maybe<VRDisplayEventReason> mReason;
+  RefPtr<VRDisplay> mDisplay;
+
+ public:
+  virtual JSObject* WrapObjectInternal(
+      JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;
+
+  static already_AddRefed<VRDisplayEvent> Constructor(
+      mozilla::dom::EventTarget* aOwner, const nsAString& aType,
+      const VRDisplayEventInit& aEventInitDict);
+
+  static already_AddRefed<VRDisplayEvent> Constructor(
+      const GlobalObject& aGlobal, const nsAString& aType,
+      const VRDisplayEventInit& aEventInitDict);
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif
diff --git a/dom/vr/VREventObserver.cpp b/dom/vr/VREventObserver.cpp
new file mode 100644
index 0000000000..e69940ef3f
--- /dev/null
+++ b/dom/vr/VREventObserver.cpp
@@ -0,0 +1,183 @@
+/* -*- 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/. */
+
+#include "VREventObserver.h"
+
+#include "nsContentUtils.h"
+#include "nsGlobalWindow.h"
+
+#include "mozilla/Telemetry.h"
+
+namespace mozilla {
+namespace dom {
+
+using namespace gfx;
+
+/**
+ * This class is used by nsGlobalWindow to implement window.onvrdisplayactivate,
+ * window.onvrdisplaydeactivate, window.onvrdisplayconnected,
+ * window.onvrdisplaydisconnected, and window.onvrdisplaypresentchange.
+ */
+VREventObserver::VREventObserver(nsGlobalWindowInner* aGlobalWindow)
+    : mWindow(aGlobalWindow),
+      mIs2DView(true),
+      mHasReset(false),
+      mStopActivity(false) {
+  MOZ_ASSERT(aGlobalWindow);
+
+  UpdateSpentTimeIn2DTelemetry(false);
+  VRManagerChild* vmc = VRManagerChild::Get();
+  if (vmc) {
+    vmc->AddListener(this);
+  }
+}
+
+VREventObserver::~VREventObserver() { DisconnectFromOwner(); }
+
+void VREventObserver::DisconnectFromOwner() {
+  // In the event that nsGlobalWindow is deallocated, VREventObserver may
+  // still be AddRef'ed elsewhere.  Ensure that we don't UAF by
+  // dereferencing mWindow.
+  UpdateSpentTimeIn2DTelemetry(true);
+  mWindow = nullptr;
+
+  // Unregister from VRManagerChild
+  if (VRManagerChild::IsCreated()) {
+    VRManagerChild* vmc = VRManagerChild::Get();
+    vmc->RemoveListener(this);
+  }
+  mStopActivity = true;
+}
+
+void VREventObserver::UpdateSpentTimeIn2DTelemetry(bool aUpdate) {
+  // mHasReset for avoiding setting the telemetry continuously
+  // for the telemetry is already been set when it is at the background.
+  // then, it would be set again when the process is exit and calling
+  // VREventObserver::DisconnectFromOwner().
+  if (mWindow && mIs2DView && aUpdate && mHasReset) {
+    // The WebVR content is closed, and we will collect the telemetry info
+    // for the users who view it in 2D view only.
+    Telemetry::Accumulate(Telemetry::WEBVR_USERS_VIEW_IN, 0);
+    Telemetry::AccumulateTimeDelta(Telemetry::WEBVR_TIME_SPENT_VIEWING_IN_2D,
+                                   mSpendTimeIn2DView);
+    mHasReset = false;
+  } else if (!aUpdate) {
+    mSpendTimeIn2DView = TimeStamp::Now();
+    mHasReset = true;
+  }
+}
+
+void VREventObserver::StartActivity() {
+  mStopActivity = false;
+  VRManagerChild* vmc = VRManagerChild::Get();
+  vmc->StartActivity();
+}
+
+void VREventObserver::StopActivity() {
+  mStopActivity = true;
+  VRManagerChild* vmc = VRManagerChild::Get();
+  vmc->StopActivity();
+}
+
+bool VREventObserver::GetStopActivityStatus() const { return mStopActivity; }
+
+void VREventObserver::NotifyAfterLoad() {
+  if (VRManagerChild::IsCreated()) {
+    VRManagerChild* vmc = VRManagerChild::Get();
+    vmc->FireDOMVRDisplayConnectEventsForLoad(this);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayMounted(uint32_t aDisplayID) {
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayActivate(aDisplayID,
+                                       VRDisplayEventReason::Mounted);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayNavigation(uint32_t aDisplayID) {
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayActivate(aDisplayID,
+                                       VRDisplayEventReason::Navigation);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayRequested(uint32_t aDisplayID) {
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayActivate(aDisplayID,
+                                       VRDisplayEventReason::Requested);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayUnmounted(uint32_t aDisplayID) {
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayDeactivate(aDisplayID,
+                                         VRDisplayEventReason::Unmounted);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayConnect(uint32_t aDisplayID) {
+  /**
+   * We do not call nsGlobalWindow::NotifyActiveVRDisplaysChanged here, as we
+   * can assume that a newly enumerated display is not presenting WebVR
+   * content.
+   */
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayConnect(aDisplayID);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayDisconnect(uint32_t aDisplayID) {
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    mWindow->NotifyActiveVRDisplaysChanged();
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayDisconnect(aDisplayID);
+  }
+}
+
+void VREventObserver::NotifyVRDisplayPresentChange(uint32_t aDisplayID) {
+  // When switching to HMD present mode, it is no longer
+  // to be a 2D view.
+  mIs2DView = false;
+
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    mWindow->NotifyActiveVRDisplaysChanged();
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->DispatchVRDisplayPresentChange(aDisplayID);
+  }
+}
+
+void VREventObserver::NotifyPresentationGenerationChanged(uint32_t aDisplayID) {
+  if (mWindow && mWindow->IsCurrentInnerWindow() && IsWebVR(aDisplayID)) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->NotifyPresentationGenerationChanged(aDisplayID);
+  }
+}
+
+void VREventObserver::NotifyEnumerationCompleted() {}
+
+void VREventObserver::NotifyDetectRuntimesCompleted() {
+  if (mWindow && mWindow->IsCurrentInnerWindow()) {
+    MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
+    mWindow->NotifyDetectXRRuntimesCompleted();
+  }
+}
+
+bool VREventObserver::IsWebVR(uint32_t aDisplayID) const {
+  VRManagerChild* vmc = VRManagerChild::Get();
+  if (vmc) {
+    return vmc->GetVRAPIMode(aDisplayID) == gfx::VRAPIMode::WebVR;
+  }
+  return true;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/VREventObserver.h b/dom/vr/VREventObserver.h
new file mode 100644
index 0000000000..e19063ca26
--- /dev/null
+++ b/dom/vr/VREventObserver.h
@@ -0,0 +1,59 @@
+/* -*- 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_VREventObserver_h
+#define mozilla_dom_VREventObserver_h
+
+#include "mozilla/dom/VRDisplayEventBinding.h"
+#include "nsISupportsImpl.h"  // for NS_INLINE_DECL_REFCOUNTING
+#include "VRManagerChild.h"
+
+class nsGlobalWindowInner;
+
+namespace mozilla {
+namespace dom {
+
+class VREventObserver final : public gfx::VRManagerEventObserver {
+ public:
+  NS_INLINE_DECL_REFCOUNTING(VREventObserver, override)
+  explicit VREventObserver(nsGlobalWindowInner* aGlobalWindow);
+
+  void NotifyAfterLoad();
+  void NotifyVRDisplayMounted(uint32_t aDisplayID) override;
+  void NotifyVRDisplayUnmounted(uint32_t aDisplayID) override;
+  void NotifyVRDisplayNavigation(uint32_t aDisplayID);
+  void NotifyVRDisplayRequested(uint32_t aDisplayID);
+  void NotifyVRDisplayConnect(uint32_t aDisplayID) override;
+  void NotifyVRDisplayDisconnect(uint32_t aDisplayID) override;
+  void NotifyVRDisplayPresentChange(uint32_t aDisplayID) override;
+  void NotifyPresentationGenerationChanged(uint32_t aDisplayID) override;
+  void NotifyEnumerationCompleted() override;
+  void NotifyDetectRuntimesCompleted() override;
+
+  void DisconnectFromOwner();
+  void UpdateSpentTimeIn2DTelemetry(bool aUpdate);
+  void StartActivity();
+  void StopActivity();
+  bool GetStopActivityStatus() const override;
+
+ private:
+  ~VREventObserver();
+
+  bool IsWebVR(uint32_t aDisplayID) const;
+
+  RefPtr<nsGlobalWindowInner> mWindow;
+  // For WebVR telemetry for tracking users who view content
+  // in the 2D view.
+  TimeStamp mSpendTimeIn2DView;
+  bool mIs2DView;
+  bool mHasReset;
+  bool mStopActivity;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_VREventObserver_h
diff --git a/dom/vr/VRServiceTest.cpp b/dom/vr/VRServiceTest.cpp
new file mode 100644
index 0000000000..473f3d1d34
--- /dev/null
+++ b/dom/vr/VRServiceTest.cpp
@@ -0,0 +1,770 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/VRServiceTest.h"
+#include "mozilla/dom/VRServiceTestBinding.h"
+#include "mozilla/dom/GamepadPoseState.h"
+#include "mozilla/dom/Promise.h"
+#include "VRManagerChild.h"
+#include "VRPuppetCommandBuffer.h"
+#include <type_traits>
+
+namespace mozilla {
+using namespace gfx;
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VRMockDisplay)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(VRMockDisplay,
+                                                  DOMEventTargetHelper)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(VRMockDisplay,
+                                                DOMEventTargetHelper)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(VRMockDisplay)
+NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
+
+NS_IMPL_ADDREF_INHERITED(VRMockDisplay, DOMEventTargetHelper)
+NS_IMPL_RELEASE_INHERITED(VRMockDisplay, DOMEventTargetHelper)
+
+namespace {
+template <class T>
+bool ReadFloat32Array(T& aDestination, const Float32Array& aSource,
+                      ErrorResult& aRv) {
+  constexpr size_t length = std::extent<T>::value;
+  aSource.ComputeState();
+  if (aSource.Length() != length) {
+    aRv.Throw(NS_ERROR_INVALID_ARG);
+    // We don't want to MOZ_ASSERT here, as that would cause the
+    // browser to crash, making it difficult to debug the problem
+    // in JS code calling this API.
+    return false;
+  }
+  for (size_t i = 0; i < length; i++) {
+    aDestination[i] = aSource.Data()[i];
+  }
+  return true;
+}
+};  // anonymous namespace
+
+VRMockDisplay::VRMockDisplay(VRServiceTest* aVRServiceTest)
+    : DOMEventTargetHelper(aVRServiceTest->GetOwner()),
+      mVRServiceTest(aVRServiceTest) {}
+
+JSObject* VRMockDisplay::WrapObject(JSContext* aCx,
+                                    JS::Handle<JSObject*> aGivenProto) {
+  return VRMockDisplay_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+VRHMDSensorState& VRMockDisplay::SensorState() const {
+  return mVRServiceTest->SystemState().sensorState;
+}
+
+VRDisplayState& VRMockDisplay::DisplayState() const {
+  return mVRServiceTest->SystemState().displayState;
+}
+
+void VRMockDisplay::Clear() {
+  VRDisplayState& displayState = DisplayState();
+  displayState.Clear();
+  VRHMDSensorState& sensorState = SensorState();
+  sensorState.Clear();
+}
+
+void VRMockDisplay::Create() {
+  Clear();
+  VRDisplayState& state = DisplayState();
+
+  strncpy(state.displayName, "Puppet HMD", kVRDisplayNameMaxLen);
+  state.eightCC = GFX_VR_EIGHTCC('P', 'u', 'p', 'p', 'e', 't', ' ', ' ');
+  state.isConnected = true;
+  state.isMounted = false;
+  state.capabilityFlags = VRDisplayCapabilityFlags::Cap_None |
+                          VRDisplayCapabilityFlags::Cap_Orientation |
+                          VRDisplayCapabilityFlags::Cap_Position |
+                          VRDisplayCapabilityFlags::Cap_External |
+                          VRDisplayCapabilityFlags::Cap_Present |
+                          VRDisplayCapabilityFlags::Cap_StageParameters |
+                          VRDisplayCapabilityFlags::Cap_MountDetection |
+                          VRDisplayCapabilityFlags::Cap_ImmersiveVR;
+  state.blendMode = VRDisplayBlendMode::Opaque;
+
+  // 1836 x 2040 resolution is arbitrary and can be overridden.
+  // This default resolution was chosen to be within range of a
+  // typical VR eye buffer size.  This value is derived by
+  // scaling a 1080x1200 per-eye panel resolution by the
+  // commonly used pre-lens-distortion pass scaling factor of 1.7x.
+  // 1.7x is commonly used in HMD's employing fresnel lenses to ensure
+  // a sufficient fragment shading rate in the peripheral area of the
+  // post-warp eye buffers.
+  state.eyeResolution.width = 1836;   // 1080 * 1.7
+  state.eyeResolution.height = 2040;  // 1200 * 1.7
+
+  for (uint32_t eye = 0; eye < VRDisplayState::NumEyes; ++eye) {
+    state.eyeTranslation[eye].x = 0.0f;
+    state.eyeTranslation[eye].y = 0.0f;
+    state.eyeTranslation[eye].z = 0.0f;
+    state.eyeFOV[eye] = gfx::VRFieldOfView(45.0, 45.0, 45.0, 45.0);
+  }
+
+  // default: 1m x 1m space, 0.75m high in seated position
+  state.stageSize.width = 1.0f;
+  state.stageSize.height = 1.0f;
+
+  state.sittingToStandingTransform[0] = 1.0f;
+  state.sittingToStandingTransform[1] = 0.0f;
+  state.sittingToStandingTransform[2] = 0.0f;
+  state.sittingToStandingTransform[3] = 0.0f;
+
+  state.sittingToStandingTransform[4] = 0.0f;
+  state.sittingToStandingTransform[5] = 1.0f;
+  state.sittingToStandingTransform[6] = 0.0f;
+  state.sittingToStandingTransform[7] = 0.0f;
+
+  state.sittingToStandingTransform[8] = 0.0f;
+  state.sittingToStandingTransform[9] = 0.0f;
+  state.sittingToStandingTransform[10] = 1.0f;
+  state.sittingToStandingTransform[11] = 0.0f;
+
+  state.sittingToStandingTransform[12] = 0.0f;
+  state.sittingToStandingTransform[13] = 0.75f;
+  state.sittingToStandingTransform[14] = 0.0f;
+  state.sittingToStandingTransform[15] = 1.0f;
+
+  VRHMDSensorState& sensorState = SensorState();
+  gfx::Quaternion rot;
+  sensorState.flags |= VRDisplayCapabilityFlags::Cap_Orientation;
+  sensorState.pose.orientation[0] = rot.x;
+  sensorState.pose.orientation[1] = rot.y;
+  sensorState.pose.orientation[2] = rot.z;
+  sensorState.pose.orientation[3] = rot.w;
+  sensorState.pose.angularVelocity[0] = 0.0f;
+  sensorState.pose.angularVelocity[1] = 0.0f;
+  sensorState.pose.angularVelocity[2] = 0.0f;
+
+  sensorState.flags |= VRDisplayCapabilityFlags::Cap_Position;
+  sensorState.pose.position[0] = 0.0f;
+  sensorState.pose.position[1] = 0.0f;
+  sensorState.pose.position[2] = 0.0f;
+  sensorState.pose.linearVelocity[0] = 0.0f;
+  sensorState.pose.linearVelocity[1] = 0.0f;
+  sensorState.pose.linearVelocity[2] = 0.0f;
+}
+
+void VRMockDisplay::SetConnected(bool aConnected) {
+  DisplayState().isConnected = aConnected;
+}
+bool VRMockDisplay::Connected() const { return DisplayState().isConnected; }
+
+void VRMockDisplay::SetMounted(bool aMounted) {
+  DisplayState().isMounted = aMounted;
+}
+
+bool VRMockDisplay::Mounted() const { return DisplayState().isMounted; }
+
+void VRMockDisplay::SetCapFlag(VRDisplayCapabilityFlags aFlag, bool aEnabled) {
+  if (aEnabled) {
+    DisplayState().capabilityFlags |= aFlag;
+  } else {
+    DisplayState().capabilityFlags &= ~aFlag;
+  }
+}
+bool VRMockDisplay::GetCapFlag(VRDisplayCapabilityFlags aFlag) const {
+  return ((DisplayState().capabilityFlags & aFlag) !=
+          VRDisplayCapabilityFlags::Cap_None);
+}
+
+void VRMockDisplay::SetCapPosition(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_Position, aEnabled);
+}
+
+void VRMockDisplay::SetCapOrientation(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_Orientation, aEnabled);
+}
+
+void VRMockDisplay::SetCapPresent(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_Present, aEnabled);
+}
+
+void VRMockDisplay::SetCapExternal(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_External, aEnabled);
+}
+
+void VRMockDisplay::SetCapAngularAcceleration(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_AngularAcceleration, aEnabled);
+}
+
+void VRMockDisplay::SetCapLinearAcceleration(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_LinearAcceleration, aEnabled);
+}
+
+void VRMockDisplay::SetCapStageParameters(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_StageParameters, aEnabled);
+}
+
+void VRMockDisplay::SetCapMountDetection(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_MountDetection, aEnabled);
+}
+
+void VRMockDisplay::SetCapPositionEmulated(bool aEnabled) {
+  SetCapFlag(VRDisplayCapabilityFlags::Cap_PositionEmulated, aEnabled);
+}
+
+void VRMockDisplay::SetEyeFOV(VREye aEye, double aUpDegree, double aRightDegree,
+                              double aDownDegree, double aLeftDegree) {
+  gfx::VRDisplayState::Eye eye = aEye == VREye::Left
+                                     ? gfx::VRDisplayState::Eye_Left
+                                     : gfx::VRDisplayState::Eye_Right;
+  VRDisplayState& state = DisplayState();
+  state.eyeFOV[eye] =
+      gfx::VRFieldOfView(aUpDegree, aRightDegree, aDownDegree, aLeftDegree);
+}
+
+void VRMockDisplay::SetEyeOffset(VREye aEye, double aOffsetX, double aOffsetY,
+                                 double aOffsetZ) {
+  gfx::VRDisplayState::Eye eye = aEye == VREye::Left
+                                     ? gfx::VRDisplayState::Eye_Left
+                                     : gfx::VRDisplayState::Eye_Right;
+  VRDisplayState& state = DisplayState();
+  state.eyeTranslation[eye].x = (float)aOffsetX;
+  state.eyeTranslation[eye].y = (float)aOffsetY;
+  state.eyeTranslation[eye].z = (float)aOffsetZ;
+}
+
+bool VRMockDisplay::CapPosition() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_Position);
+}
+
+bool VRMockDisplay::CapOrientation() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_Orientation);
+}
+
+bool VRMockDisplay::CapPresent() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_Present);
+}
+
+bool VRMockDisplay::CapExternal() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_External);
+}
+
+bool VRMockDisplay::CapAngularAcceleration() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_AngularAcceleration);
+}
+
+bool VRMockDisplay::CapLinearAcceleration() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_LinearAcceleration);
+}
+
+bool VRMockDisplay::CapStageParameters() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_StageParameters);
+}
+
+bool VRMockDisplay::CapMountDetection() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_MountDetection);
+}
+
+bool VRMockDisplay::CapPositionEmulated() const {
+  return GetCapFlag(VRDisplayCapabilityFlags::Cap_PositionEmulated);
+}
+
+void VRMockDisplay::SetEyeResolution(uint32_t aRenderWidth,
+                                     uint32_t aRenderHeight) {
+  DisplayState().eyeResolution.width = aRenderWidth;
+  DisplayState().eyeResolution.height = aRenderHeight;
+}
+
+void VRMockDisplay::SetStageSize(double aWidth, double aHeight) {
+  VRDisplayState& displayState = DisplayState();
+  displayState.stageSize.width = (float)aWidth;
+  displayState.stageSize.height = (float)aHeight;
+}
+
+void VRMockDisplay::SetSittingToStandingTransform(
+    const Float32Array& aTransform, ErrorResult& aRv) {
+  Unused << ReadFloat32Array(DisplayState().sittingToStandingTransform,
+                             aTransform, aRv);
+}
+
+void VRMockDisplay::SetPose(const Nullable<Float32Array>& aPosition,
+                            const Nullable<Float32Array>& aLinearVelocity,
+                            const Nullable<Float32Array>& aLinearAcceleration,
+                            const Nullable<Float32Array>& aOrientation,
+                            const Nullable<Float32Array>& aAngularVelocity,
+                            const Nullable<Float32Array>& aAngularAcceleration,
+                            ErrorResult& aRv) {
+  VRHMDSensorState& sensorState = mVRServiceTest->SystemState().sensorState;
+  sensorState.Clear();
+  sensorState.flags = VRDisplayCapabilityFlags::Cap_None;
+  // sensorState.timestamp will be set automatically during
+  // puppet script execution
+
+  if (!aOrientation.IsNull()) {
+    if (!ReadFloat32Array(sensorState.pose.orientation, aOrientation.Value(),
+                          aRv)) {
+      return;
+    }
+    sensorState.flags |= VRDisplayCapabilityFlags::Cap_Orientation;
+  }
+  if (!aAngularVelocity.IsNull()) {
+    if (!ReadFloat32Array(sensorState.pose.angularVelocity,
+                          aAngularVelocity.Value(), aRv)) {
+      return;
+    }
+    sensorState.flags |= VRDisplayCapabilityFlags::Cap_AngularAcceleration;
+  }
+  if (!aAngularAcceleration.IsNull()) {
+    if (!ReadFloat32Array(sensorState.pose.angularAcceleration,
+                          aAngularAcceleration.Value(), aRv)) {
+      return;
+    }
+    sensorState.flags |= VRDisplayCapabilityFlags::Cap_AngularAcceleration;
+  }
+  if (!aPosition.IsNull()) {
+    if (!ReadFloat32Array(sensorState.pose.position, aPosition.Value(), aRv)) {
+      return;
+    }
+    sensorState.flags |= VRDisplayCapabilityFlags::Cap_Position;
+  }
+  if (!aLinearVelocity.IsNull()) {
+    if (!ReadFloat32Array(sensorState.pose.linearVelocity,
+                          aLinearVelocity.Value(), aRv)) {
+      return;
+    }
+    sensorState.flags |= VRDisplayCapabilityFlags::Cap_LinearAcceleration;
+  }
+  if (!aLinearAcceleration.IsNull()) {
+    if (!ReadFloat32Array(sensorState.pose.linearAcceleration,
+                          aLinearAcceleration.Value(), aRv)) {
+      return;
+    }
+    sensorState.flags |= VRDisplayCapabilityFlags::Cap_LinearAcceleration;
+  }
+}
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VRMockController)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(VRMockController,
+                                                  DOMEventTargetHelper)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(VRMockController,
+                                                DOMEventTargetHelper)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(VRMockController)
+NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
+
+NS_IMPL_ADDREF_INHERITED(VRMockController, DOMEventTargetHelper)
+NS_IMPL_RELEASE_INHERITED(VRMockController, DOMEventTargetHelper)
+
+VRMockController::VRMockController(VRServiceTest* aVRServiceTest,
+                                   uint32_t aControllerIdx)
+    : DOMEventTargetHelper(aVRServiceTest->GetOwner()),
+      mVRServiceTest(aVRServiceTest),
+      mControllerIdx(aControllerIdx) {
+  MOZ_ASSERT(aControllerIdx < kVRControllerMaxCount);
+}
+
+JSObject* VRMockController::WrapObject(JSContext* aCx,
+                                       JS::Handle<JSObject*> aGivenProto) {
+  return VRMockController_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+VRControllerState& VRMockController::ControllerState() const {
+  return mVRServiceTest->SystemState().controllerState[mControllerIdx];
+}
+
+void VRMockController::Create() {
+  // Initialize with a 6dof, left-handed gamepad with one haptic actuator
+  // Tests are expected to modify the controller before it is sent to the
+  // puppet.
+  Clear();
+  VRControllerState& state = ControllerState();
+  strncpy(state.controllerName, "Puppet Gamepad", kVRControllerNameMaxLen);
+  state.hand = GamepadHand::Left;
+  state.flags = GamepadCapabilityFlags::Cap_Position |
+                GamepadCapabilityFlags::Cap_Orientation;
+  state.numButtons = 1;
+  state.numHaptics = 1;
+  state.triggerValue[0] = 0.0f;
+}
+
+void VRMockController::Clear() {
+  mVRServiceTest->ClearController(mControllerIdx);
+}
+
+void VRMockController::SetCapFlag(GamepadCapabilityFlags aFlag, bool aEnabled) {
+  if (aEnabled) {
+    ControllerState().flags |= aFlag;
+  } else {
+    ControllerState().flags &= ~aFlag;
+  }
+}
+bool VRMockController::GetCapFlag(GamepadCapabilityFlags aFlag) const {
+  return (ControllerState().flags & aFlag) != GamepadCapabilityFlags::Cap_None;
+}
+
+void VRMockController::SetHand(GamepadHand aHand) {
+  ControllerState().hand = aHand;
+}
+
+GamepadHand VRMockController::Hand() const { return ControllerState().hand; }
+
+void VRMockController::SetCapPosition(bool aEnabled) {
+  SetCapFlag(GamepadCapabilityFlags::Cap_Position, aEnabled);
+}
+
+bool VRMockController::CapPosition() const {
+  return GetCapFlag(GamepadCapabilityFlags::Cap_Position);
+}
+
+void VRMockController::SetCapOrientation(bool aEnabled) {
+  SetCapFlag(GamepadCapabilityFlags::Cap_Orientation, aEnabled);
+}
+
+bool VRMockController::CapOrientation() const {
+  return GetCapFlag(GamepadCapabilityFlags::Cap_Orientation);
+}
+
+void VRMockController::SetCapAngularAcceleration(bool aEnabled) {
+  SetCapFlag(GamepadCapabilityFlags::Cap_AngularAcceleration, aEnabled);
+}
+
+bool VRMockController::CapAngularAcceleration() const {
+  return GetCapFlag(GamepadCapabilityFlags::Cap_AngularAcceleration);
+}
+
+void VRMockController::SetCapLinearAcceleration(bool aEnabled) {
+  SetCapFlag(GamepadCapabilityFlags::Cap_LinearAcceleration, aEnabled);
+}
+
+bool VRMockController::CapLinearAcceleration() const {
+  return GetCapFlag(GamepadCapabilityFlags::Cap_LinearAcceleration);
+}
+
+void VRMockController::SetAxisCount(uint32_t aCount) {
+  MOZ_ASSERT(aCount <= kVRControllerMaxAxis);
+  ControllerState().numAxes = aCount;
+}
+
+uint32_t VRMockController::AxisCount() const {
+  return ControllerState().numAxes;
+}
+
+void VRMockController::SetButtonCount(uint32_t aCount) {
+  MOZ_ASSERT(aCount <= kVRControllerMaxButtons);
+  ControllerState().numButtons = aCount;
+}
+
+uint32_t VRMockController::ButtonCount() const {
+  return ControllerState().numButtons;
+}
+
+void VRMockController::SetHapticCount(uint32_t aCount) {
+  ControllerState().numHaptics = aCount;
+}
+
+uint32_t VRMockController::HapticCount() const {
+  return ControllerState().numHaptics;
+}
+
+void VRMockController::SetButtonPressed(uint32_t aButtonIdx, bool aPressed) {
+  MOZ_ASSERT(aButtonIdx < kVRControllerMaxButtons);
+  if (aPressed) {
+    ControllerState().buttonPressed |= (1 << aButtonIdx);
+  } else {
+    ControllerState().buttonPressed &= ~(1 << aButtonIdx);
+  }
+}
+
+void VRMockController::SetButtonTouched(uint32_t aButtonIdx, bool aTouched) {
+  MOZ_ASSERT(aButtonIdx < kVRControllerMaxButtons);
+  if (aTouched) {
+    ControllerState().buttonTouched |= (1 << aButtonIdx);
+  } else {
+    ControllerState().buttonTouched &= ~(1 << aButtonIdx);
+  }
+}
+
+void VRMockController::SetButtonTrigger(uint32_t aButtonIdx, double aTrigger) {
+  MOZ_ASSERT(aButtonIdx < kVRControllerMaxButtons);
+
+  ControllerState().triggerValue[aButtonIdx] = (float)aTrigger;
+}
+
+void VRMockController::SetAxisValue(uint32_t aAxisIdx, double aValue) {
+  MOZ_ASSERT(aAxisIdx < kVRControllerMaxAxis);
+  ControllerState().axisValue[aAxisIdx] = (float)aValue;
+}
+
+void VRMockController::SetPose(
+    const Nullable<Float32Array>& aPosition,
+    const Nullable<Float32Array>& aLinearVelocity,
+    const Nullable<Float32Array>& aLinearAcceleration,
+    const Nullable<Float32Array>& aOrientation,
+    const Nullable<Float32Array>& aAngularVelocity,
+    const Nullable<Float32Array>& aAngularAcceleration, ErrorResult& aRv) {
+  VRControllerState& controllerState = ControllerState();
+  controllerState.flags = GamepadCapabilityFlags::Cap_None;
+
+  if (!aOrientation.IsNull()) {
+    if (!ReadFloat32Array(controllerState.pose.orientation,
+                          aOrientation.Value(), aRv)) {
+      return;
+    }
+    controllerState.flags |= GamepadCapabilityFlags::Cap_Orientation;
+  }
+  if (!aAngularVelocity.IsNull()) {
+    if (!ReadFloat32Array(controllerState.pose.angularVelocity,
+                          aAngularVelocity.Value(), aRv)) {
+      return;
+    }
+    controllerState.flags |= GamepadCapabilityFlags::Cap_AngularAcceleration;
+  }
+  if (!aAngularAcceleration.IsNull()) {
+    if (!ReadFloat32Array(controllerState.pose.angularAcceleration,
+                          aAngularAcceleration.Value(), aRv)) {
+      return;
+    }
+    controllerState.flags |= GamepadCapabilityFlags::Cap_AngularAcceleration;
+  }
+  if (!aPosition.IsNull()) {
+    if (!ReadFloat32Array(controllerState.pose.position, aPosition.Value(),
+                          aRv)) {
+      return;
+    }
+    controllerState.flags |= GamepadCapabilityFlags::Cap_Position;
+  }
+  if (!aLinearVelocity.IsNull()) {
+    if (!ReadFloat32Array(controllerState.pose.linearVelocity,
+                          aLinearVelocity.Value(), aRv)) {
+      return;
+    }
+    controllerState.flags |= GamepadCapabilityFlags::Cap_LinearAcceleration;
+  }
+  if (!aLinearAcceleration.IsNull()) {
+    if (!ReadFloat32Array(controllerState.pose.linearAcceleration,
+                          aLinearAcceleration.Value(), aRv)) {
+      return;
+    }
+    controllerState.flags |= GamepadCapabilityFlags::Cap_LinearAcceleration;
+  }
+}
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(VRServiceTest)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(VRServiceTest,
+                                                  DOMEventTargetHelper)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(VRServiceTest,
+                                                DOMEventTargetHelper)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(VRServiceTest)
+NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
+
+NS_IMPL_ADDREF_INHERITED(VRServiceTest, DOMEventTargetHelper)
+NS_IMPL_RELEASE_INHERITED(VRServiceTest, DOMEventTargetHelper)
+
+JSObject* VRServiceTest::WrapObject(JSContext* aCx,
+                                    JS::Handle<JSObject*> aGivenProto) {
+  return VRServiceTest_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+// static
+already_AddRefed<VRServiceTest> VRServiceTest::CreateTestService(
+    nsPIDOMWindowInner* aWindow) {
+  MOZ_ASSERT(aWindow);
+  RefPtr<VRServiceTest> service = new VRServiceTest(aWindow);
+  return service.forget();
+}
+
+VRServiceTest::VRServiceTest(nsPIDOMWindowInner* aWindow)
+    : mWindow(aWindow), mPendingState{}, mEncodedState{}, mShuttingDown(false) {
+  mDisplay = new VRMockDisplay(this);
+  for (int i = 0; i < kVRControllerMaxCount; i++) {
+    mControllers.AppendElement(new VRMockController(this, i));
+  }
+  ClearAll();
+}
+
+gfx::VRSystemState& VRServiceTest::SystemState() { return mPendingState; }
+
+VRMockDisplay* VRServiceTest::GetVRDisplay() { return mDisplay; }
+
+VRMockController* VRServiceTest::GetVRController(uint32_t aControllerIdx,
+                                                 ErrorResult& aRv) {
+  if (aControllerIdx >= kVRControllerMaxCount) {
+    aRv.Throw(NS_ERROR_INVALID_ARG);
+    return nullptr;
+  }
+  return mControllers[aControllerIdx];
+}
+
+void VRServiceTest::Shutdown() {
+  MOZ_ASSERT(!mShuttingDown);
+  mShuttingDown = true;
+  mWindow = nullptr;
+}
+
+void VRServiceTest::AddCommand(uint64_t aCommand) {
+  EncodeData();
+  mCommandBuffer.AppendElement(aCommand);
+}
+
+void VRServiceTest::End() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_End);
+}
+
+void VRServiceTest::ClearAll() {
+  memset(&mPendingState, 0, sizeof(VRSystemState));
+  memset(&mEncodedState, 0, sizeof(VRSystemState));
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_ClearAll);
+}
+
+void VRServiceTest::ClearController(uint32_t aControllerIdx) {
+  MOZ_ASSERT(aControllerIdx < kVRControllerMaxCount);
+  mPendingState.controllerState[aControllerIdx].Clear();
+  mEncodedState.controllerState[aControllerIdx].Clear();
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_ClearController |
+             (uint64_t)aControllerIdx);
+}
+
+void VRServiceTest::Timeout(uint32_t aDuration) {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_Timeout |
+             (uint64_t)aDuration);
+}
+
+void VRServiceTest::Wait(uint32_t aDuration) {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_Wait | (uint64_t)aDuration);
+}
+
+void VRServiceTest::WaitHapticIntensity(uint32_t aControllerIdx,
+                                        uint32_t aHapticIdx, double aIntensity,
+                                        ErrorResult& aRv) {
+  if (aControllerIdx >= kVRControllerMaxCount) {
+    aRv.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+  if (aHapticIdx >= kVRHapticsMaxCount) {
+    aRv.Throw(NS_ERROR_INVALID_ARG);
+    return;
+  }
+  // convert to 16.16 fixed point.  This must match conversion in
+  // VRPuppetCommandBuffer::RunCommand
+  uint64_t iIntensity = round((float)aIntensity * (1 << 16));
+  if (iIntensity > 0xffffffff) {
+    iIntensity = 0xffffffff;
+  }
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_WaitHapticIntensity |
+             ((uint64_t)aControllerIdx << 40) | ((uint64_t)aHapticIdx << 32) |
+             iIntensity);
+}
+
+void VRServiceTest::WaitSubmit() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_WaitSubmit);
+}
+
+void VRServiceTest::WaitPresentationStart() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_WaitPresentationStart);
+}
+void VRServiceTest::WaitPresentationEnd() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_WaitPresentationEnd);
+}
+
+void VRServiceTest::EncodeData() {
+  VRPuppetCommandBuffer::EncodeStruct(
+      mCommandBuffer, (uint8_t*)&mPendingState.displayState,
+      (uint8_t*)&mEncodedState.displayState, sizeof(VRDisplayState),
+      VRPuppet_Command::VRPuppet_UpdateDisplay);
+  VRPuppetCommandBuffer::EncodeStruct(
+      mCommandBuffer, (uint8_t*)&mPendingState.sensorState,
+      (uint8_t*)&mEncodedState.sensorState, sizeof(VRHMDSensorState),
+      VRPuppet_Command::VRPuppet_UpdateSensor);
+  VRPuppetCommandBuffer::EncodeStruct(
+      mCommandBuffer, (uint8_t*)&mPendingState.controllerState,
+      (uint8_t*)&mEncodedState.controllerState,
+      sizeof(VRControllerState) * kVRControllerMaxCount,
+      VRPuppet_Command::VRPuppet_UpdateControllers);
+}
+
+void VRServiceTest::CaptureFrame() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_CaptureFrame);
+}
+
+void VRServiceTest::AcknowledgeFrame() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_AcknowledgeFrame);
+}
+
+void VRServiceTest::RejectFrame() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_RejectFrame);
+}
+
+void VRServiceTest::StartTimer() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_StartTimer);
+}
+
+void VRServiceTest::StopTimer() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_StopTimer);
+}
+
+void VRServiceTest::Commit() {
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_Commit);
+}
+
+already_AddRefed<Promise> VRServiceTest::Run(ErrorResult& aRv) {
+  if (mShuttingDown) {
+    return nullptr;
+  }
+
+  AddCommand((uint64_t)VRPuppet_Command::VRPuppet_End);
+
+  RefPtr<dom::Promise> runPuppetPromise =
+      Promise::Create(mWindow->AsGlobal(), aRv);
+  if (NS_WARN_IF(aRv.Failed())) {
+    return nullptr;
+  }
+
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  vm->RunPuppet(mCommandBuffer, runPuppetPromise, aRv);
+  if (NS_WARN_IF(aRv.Failed())) {
+    return nullptr;
+  }
+
+  mCommandBuffer.Clear();
+
+  return runPuppetPromise.forget();
+}
+
+already_AddRefed<Promise> VRServiceTest::Reset(ErrorResult& aRv) {
+  if (mShuttingDown) {
+    return nullptr;
+  }
+
+  RefPtr<dom::Promise> resetPuppetPromise =
+      Promise::Create(mWindow->AsGlobal(), aRv);
+  if (NS_WARN_IF(aRv.Failed())) {
+    return nullptr;
+  }
+
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  vm->ResetPuppet(resetPuppetPromise, aRv);
+  if (NS_WARN_IF(aRv.Failed())) {
+    return nullptr;
+  }
+
+  memset(&mPendingState, 0, sizeof(VRSystemState));
+  memset(&mEncodedState, 0, sizeof(VRSystemState));
+  mCommandBuffer.Clear();
+
+  return resetPuppetPromise.forget();
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/VRServiceTest.h b/dom/vr/VRServiceTest.h
new file mode 100644
index 0000000000..b397108f6f
--- /dev/null
+++ b/dom/vr/VRServiceTest.h
@@ -0,0 +1,206 @@
+/* -*- 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_VRServiceTest_h_
+#define mozilla_dom_VRServiceTest_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/TypedArray.h"
+#include "mozilla/dom/VRServiceTestBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace gfx {
+enum class VRDisplayCapabilityFlags : uint16_t;
+enum class VRPuppet_Command : uint64_t;
+}  // namespace gfx
+namespace dom {
+enum class GamepadCapabilityFlags : uint16_t;
+
+class VRMockDisplay final : public DOMEventTargetHelper {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(VRMockDisplay, DOMEventTargetHelper)
+
+  explicit VRMockDisplay(VRServiceTest* aVRServiceTest);
+
+  void Create();
+  void Clear();
+
+  void SetConnected(bool aConnected);
+  bool Connected() const;
+  void SetMounted(bool aMounted);
+  bool Mounted() const;
+  void SetCapPosition(bool aEnabled);
+  bool CapPosition() const;
+  void SetCapOrientation(bool aEnabled);
+  bool CapOrientation() const;
+  void SetCapPresent(bool aEnabled);
+  bool CapPresent() const;
+  void SetCapExternal(bool aEnabled);
+  bool CapExternal() const;
+  void SetCapAngularAcceleration(bool aEnabled);
+  bool CapAngularAcceleration() const;
+  void SetCapLinearAcceleration(bool aEnabled);
+  bool CapLinearAcceleration() const;
+  void SetCapStageParameters(bool aEnabled);
+  bool CapStageParameters() const;
+  void SetCapMountDetection(bool aEnabled);
+  bool CapMountDetection() const;
+  void SetCapPositionEmulated(bool aEnabled);
+  bool CapPositionEmulated() const;
+  void SetEyeFOV(VREye aEye, double aUpDegree, double aRightDegree,
+                 double aDownDegree, double aLeftDegree);
+  void SetEyeOffset(VREye aEye, double aOffsetX, double aOffsetY,
+                    double aOffsetZ);
+  void SetEyeResolution(uint32_t aRenderWidth, uint32_t aRenderHeight);
+  void SetStageSize(double aWidth, double aHeight);
+  void SetSittingToStandingTransform(const Float32Array& aTransform,
+                                     ErrorResult& aRv);
+  void SetPose(const Nullable<Float32Array>& aPosition,
+               const Nullable<Float32Array>& aLinearVelocity,
+               const Nullable<Float32Array>& aLinearAcceleration,
+               const Nullable<Float32Array>& aOrientation,
+               const Nullable<Float32Array>& aAngularVelocity,
+               const Nullable<Float32Array>& aAngularAcceleration,
+               ErrorResult& aRv);
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+ private:
+  ~VRMockDisplay() = default;
+  gfx::VRDisplayState& DisplayState() const;
+  gfx::VRHMDSensorState& SensorState() const;
+  void SetCapFlag(gfx::VRDisplayCapabilityFlags aFlag, bool aEnabled);
+  bool GetCapFlag(gfx::VRDisplayCapabilityFlags aFlag) const;
+
+  RefPtr<VRServiceTest> mVRServiceTest;
+};
+
+class VRMockController : public DOMEventTargetHelper {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(VRMockController,
+                                           DOMEventTargetHelper)
+
+  VRMockController(VRServiceTest* aVRServiceTest, uint32_t aControllerIdx);
+  void Create();
+  void Clear();
+  void SetHand(GamepadHand aHand);
+  GamepadHand Hand() const;
+  void SetCapPosition(bool aEnabled);
+  bool CapPosition() const;
+  void SetCapOrientation(bool aEnabled);
+  bool CapOrientation() const;
+  void SetCapAngularAcceleration(bool aEnabled);
+  bool CapAngularAcceleration() const;
+  void SetCapLinearAcceleration(bool aEnabled);
+  bool CapLinearAcceleration() const;
+  void SetAxisCount(uint32_t aCount);
+  uint32_t AxisCount() const;
+  void SetButtonCount(uint32_t aCount);
+  uint32_t ButtonCount() const;
+  void SetHapticCount(uint32_t aCount);
+  uint32_t HapticCount() const;
+  void SetButtonPressed(uint32_t aButtonIdx, bool aPressed);
+  void SetButtonTouched(uint32_t aButtonIdx, bool aTouched);
+  void SetButtonTrigger(uint32_t aButtonIdx, double aTrigger);
+  void SetAxisValue(uint32_t aAxisIdx, double aValue);
+  void SetPose(const Nullable<Float32Array>& aPosition,
+               const Nullable<Float32Array>& aLinearVelocity,
+               const Nullable<Float32Array>& aLinearAcceleration,
+               const Nullable<Float32Array>& aOrientation,
+               const Nullable<Float32Array>& aAngularVelocity,
+               const Nullable<Float32Array>& aAngularAcceleration,
+               ErrorResult& aRv);
+
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+ private:
+  ~VRMockController() = default;
+  gfx::VRControllerState& ControllerState() const;
+  void SetCapFlag(GamepadCapabilityFlags aFlag, bool aEnabled);
+  bool GetCapFlag(GamepadCapabilityFlags aFlag) const;
+  RefPtr<VRServiceTest> mVRServiceTest;
+  uint32_t mControllerIdx;
+};
+
+class VRServiceTest final : public DOMEventTargetHelper {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(VRServiceTest, DOMEventTargetHelper)
+
+  // WebIDL interface
+
+  void ClearAll();
+  void ClearController(uint32_t aControllerIdx);
+  void Commit();
+  void End();
+  already_AddRefed<Promise> Run(ErrorResult& aRv);
+  already_AddRefed<Promise> Reset(ErrorResult& aRv);
+  VRMockDisplay* GetVRDisplay();
+  VRMockController* GetVRController(uint32_t aControllerIdx, ErrorResult& aRv);
+  void Timeout(uint32_t aDuration);
+  void Wait(uint32_t aDuration);
+  void WaitSubmit();
+  void WaitPresentationStart();
+  void WaitPresentationEnd();
+  void WaitHapticIntensity(uint32_t aControllerIdx, uint32_t aHapticIdx,
+                           double aIntensity, ErrorResult& aRv);
+  void CaptureFrame();
+  void AcknowledgeFrame();
+  void RejectFrame();
+  void StartTimer();
+  void StopTimer();
+
+  // Implementation
+  void Shutdown();
+  void AddCommand(uint64_t aCommand);
+  static already_AddRefed<VRServiceTest> CreateTestService(
+      nsPIDOMWindowInner* aWindow);
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+  gfx::VRSystemState& SystemState();
+
+ private:
+  explicit VRServiceTest(nsPIDOMWindowInner* aWindow);
+  ~VRServiceTest() = default;
+  void EncodeData();
+
+  RefPtr<VRMockDisplay> mDisplay;
+  nsTArray<RefPtr<VRMockController>> mControllers;
+  nsCOMPtr<nsPIDOMWindowInner> mWindow;
+  // mPendingState records the state of the emulated VR hardware, including
+  // changes that have not yet been committed to the command buffer.
+  gfx::VRSystemState mPendingState;
+  // mEncodedState records the state of the emulate VR hardware at the end
+  // of the last committed transaction, submitted with VRServiceTest::Commit().
+  // mPendingState represents the resulting state if all of the commands in
+  // mCommandBuffer have been played back.
+  gfx::VRSystemState mEncodedState;
+  // mCommandBuffer encodes a sequence of steps to be executed asynchronously by
+  // the simulated VR hardware.  The steps are encoded as a stream of uint64's,
+  // using the format described in gfx/vr/VRPuppetCommandBuffer.h
+  // mCommandBuffer includes only complete transactions, which will be played
+  // back such that multiple values in VRSystemState will be updated atomically.
+  // When the command buffer is submitted to the PuppetSession, with
+  // VRServiceTest::Run(), it is cleared  to ensure that the commands are not
+  // sent redundantly in subsequent VRServicetest::Run() calls.
+  // VRServiceTest::Commit() will perform a binary comparison of mPendingState
+  // and mEncodedState to determine what instructions need to be appended to
+  // mCommandBuffer.
+  // VRServiceTest::Reset() will effectively cancel all transactions and clear
+  // mCommandBuffer before submitting the reset request to the PuppetSession.
+  nsTArray<uint64_t> mCommandBuffer;
+  bool mShuttingDown;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_VRServiceTest_h_
diff --git a/dom/vr/XRBoundedReferenceSpace.cpp b/dom/vr/XRBoundedReferenceSpace.cpp
new file mode 100644
index 0000000000..9b77a8b57e
--- /dev/null
+++ b/dom/vr/XRBoundedReferenceSpace.cpp
@@ -0,0 +1,75 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRBoundedReferenceSpace.h"
+#include "mozilla/dom/XRRigidTransform.h"
+#include "mozilla/dom/DOMPoint.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+XRBoundedReferenceSpace::XRBoundedReferenceSpace(nsIGlobalObject* aParent,
+                                                 XRSession* aSession,
+                                                 XRNativeOrigin* aNativeOrigin)
+    : XRReferenceSpace(aParent, aSession, aNativeOrigin,
+                       XRReferenceSpaceType::Bounded_floor) {}
+
+JSObject* XRBoundedReferenceSpace::WrapObject(
+    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
+  return XRBoundedReferenceSpace_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+void XRBoundedReferenceSpace::GetBoundsGeometry(
+    nsTArray<RefPtr<DOMPointReadOnly>>& result) {
+  const auto size =
+      mSession->GetDisplayClient()->GetDisplayInfo().GetStageSize();
+  if (size.width == 0 || size.height == 0) {
+    return;
+  }
+
+  // https://immersive-web.github.io/webxr/#dom-xrboundedreferencespace-boundsgeometry
+  // bounds geometry must be premultiplied by the inverse of the origin offset.
+  gfx::PointDouble3D offset = mNativeOrigin->GetPosition();
+
+  const auto addPoint = [&](const double x, const double z) {
+    RefPtr<DOMPointReadOnly> obj = new DOMPointReadOnly(
+        GetParentObject(), x - offset.x, 0.0f, z - offset.z, 1.0f);
+    result.EmplaceBack(obj);
+  };
+
+  addPoint(-size.width * 0.5f, size.height * 0.5f);
+  addPoint(size.width * 0.5f, size.height * 0.5f);
+  addPoint(size.width * 0.5f, -size.height * 0.5f);
+  addPoint(-size.width * 0.5f, -size.height * 0.5f);
+
+  // TODO (Bug 1611526): Support WebXR bounded reference spaces
+}
+
+already_AddRefed<XRReferenceSpace>
+XRBoundedReferenceSpace::GetOffsetReferenceSpace(
+    const XRRigidTransform& aOriginOffset) {
+  RefPtr<XRBoundedReferenceSpace> offsetReferenceSpace =
+      new XRBoundedReferenceSpace(GetParentObject(), mSession, mNativeOrigin);
+
+  // https://immersive-web.github.io/webxr/#multiply-transforms
+  // An XRRigidTransform is essentially a rotation followed by a translation
+  gfx::QuaternionDouble otherOrientation = aOriginOffset.RawOrientation();
+  // The resulting rotation is the two combined
+  offsetReferenceSpace->mOriginOffsetOrientation =
+      mOriginOffsetOrientation * otherOrientation;
+  // We first apply the rotation of aOriginOffset to
+  // mOriginOffsetPosition offset, then translate by the offset of
+  // aOriginOffset
+  offsetReferenceSpace->mOriginOffsetPosition =
+      otherOrientation.RotatePoint(mOriginOffsetPosition) +
+      aOriginOffset.RawPosition();
+
+  return offsetReferenceSpace.forget();
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRBoundedReferenceSpace.h b/dom/vr/XRBoundedReferenceSpace.h
new file mode 100644
index 0000000000..3ecc9d40d9
--- /dev/null
+++ b/dom/vr/XRBoundedReferenceSpace.h
@@ -0,0 +1,44 @@
+/* -*- 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_XRBoundedReferenceSpace_h_
+#define mozilla_dom_XRBoundedReferenceSpace_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "mozilla/dom/XRReferenceSpace.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class DOMPointReadOnly;
+class XRSession;
+
+class XRBoundedReferenceSpace final : public XRReferenceSpace {
+ public:
+  explicit XRBoundedReferenceSpace(nsIGlobalObject* aParent,
+                                   XRSession* aSession,
+                                   XRNativeOrigin* aNativeOrigin);
+
+  // WebIDL Boilerplate
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  void GetBoundsGeometry(nsTArray<RefPtr<DOMPointReadOnly>>& result);
+  already_AddRefed<XRReferenceSpace> GetOffsetReferenceSpace(
+      const XRRigidTransform& aOriginOffset) override;
+
+ protected:
+  virtual ~XRBoundedReferenceSpace() = default;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRBoundedReferenceSpace_h_
diff --git a/dom/vr/XRFrame.cpp b/dom/vr/XRFrame.cpp
new file mode 100644
index 0000000000..f90d9e0b71
--- /dev/null
+++ b/dom/vr/XRFrame.cpp
@@ -0,0 +1,203 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRFrame.h"
+#include "mozilla/dom/XRRenderState.h"
+#include "mozilla/dom/XRRigidTransform.h"
+#include "mozilla/dom/XRViewerPose.h"
+#include "mozilla/dom/XRView.h"
+#include "mozilla/dom/XRReferenceSpace.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(XRFrame, mParent, mSession)
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(XRFrame, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(XRFrame, Release)
+
+XRFrame::XRFrame(nsISupports* aParent, XRSession* aXRSession)
+    : mParent(aParent),
+      mSession(aXRSession),
+      mActive(false),
+      mAnimationFrame(false) {}
+
+JSObject* XRFrame::WrapObject(JSContext* aCx,
+                              JS::Handle<JSObject*> aGivenProto) {
+  return XRFrame_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+XRSession* XRFrame::Session() { return mSession; }
+
+already_AddRefed<XRViewerPose> XRFrame::GetViewerPose(
+    const XRReferenceSpace& aReferenceSpace, ErrorResult& aRv) {
+  if (!mActive || !mAnimationFrame) {
+    aRv.ThrowInvalidStateError(
+        "GetViewerPose can only be called on an XRFrame during an "
+        "XRSession.requestAnimationFrame callback.");
+    return nullptr;
+  }
+
+  if (aReferenceSpace.GetSession() != mSession) {
+    aRv.ThrowInvalidStateError(
+        "The XRReferenceSpace passed to GetViewerPose must belong to the "
+        "XRSession that GetViewerPose is called on.");
+    return nullptr;
+  }
+
+  // TODO (Bug 1616390) - Validate that poses may be reported:
+  // https://immersive-web.github.io/webxr/#poses-may-be-reported
+
+  // TODO (Bug 1616393) - Check if poses must be limited:
+  // https://immersive-web.github.io/webxr/#poses-must-be-limited
+
+  bool emulatedPosition = aReferenceSpace.IsPositionEmulated();
+
+  XRRenderState* renderState = mSession->GetActiveRenderState();
+  float depthNear = (float)renderState->DepthNear();
+  float depthFar = (float)renderState->DepthFar();
+
+  RefPtr<XRViewerPose> viewerPose;
+
+  gfx::VRDisplayClient* display = mSession->GetDisplayClient();
+  if (display) {
+    // Have a VRDisplayClient
+    const gfx::VRDisplayInfo& displayInfo =
+        mSession->GetDisplayClient()->GetDisplayInfo();
+    const gfx::VRHMDSensorState& sensorState = display->GetSensorState();
+
+    gfx::PointDouble3D viewerPosition = gfx::PointDouble3D(
+        sensorState.pose.position[0], sensorState.pose.position[1],
+        sensorState.pose.position[2]);
+    gfx::QuaternionDouble viewerOrientation = gfx::QuaternionDouble(
+        sensorState.pose.orientation[0], sensorState.pose.orientation[1],
+        sensorState.pose.orientation[2], sensorState.pose.orientation[3]);
+
+    gfx::Matrix4x4Double headTransform;
+    headTransform.SetRotationFromQuaternion(viewerOrientation);
+    headTransform.PostTranslate(viewerPosition);
+
+    gfx::Matrix4x4Double originTransform;
+    originTransform.SetRotationFromQuaternion(
+        aReferenceSpace.GetEffectiveOriginOrientation().Inverse());
+    originTransform.PreTranslate(-aReferenceSpace.GetEffectiveOriginPosition());
+
+    headTransform *= originTransform;
+
+    viewerPose = mSession->PooledViewerPose(headTransform, emulatedPosition);
+
+    auto updateEye = [&](int32_t viewIndex, gfx::VRDisplayState::Eye eye) {
+      auto offset = displayInfo.GetEyeTranslation(eye);
+      auto eyeFromHead = gfx::Matrix4x4Double::Translation(
+          gfx::PointDouble3D(offset.x, offset.y, offset.z));
+      auto eyeTransform = eyeFromHead * headTransform;
+      gfx::PointDouble3D eyePosition;
+      gfx::QuaternionDouble eyeRotation;
+      gfx::PointDouble3D eyeScale;
+      eyeTransform.Decompose(eyePosition, eyeRotation, eyeScale);
+
+      const gfx::VRFieldOfView fov = displayInfo.mDisplayState.eyeFOV[eye];
+      gfx::Matrix4x4 projection =
+          fov.ConstructProjectionMatrix(depthNear, depthFar, true);
+      viewerPose->GetEye(viewIndex)->Update(eyePosition, eyeRotation,
+                                            projection);
+    };
+
+    updateEye(0, gfx::VRDisplayState::Eye_Left);
+    updateEye(1, gfx::VRDisplayState::Eye_Right);
+  } else {
+    auto inlineVerticalFov = renderState->GetInlineVerticalFieldOfView();
+    const double fov =
+        inlineVerticalFov.IsNull() ? M_PI * 0.5f : inlineVerticalFov.Value();
+    HTMLCanvasElement* canvas = renderState->GetOutputCanvas();
+    float aspect = 1.0f;
+    if (canvas) {
+      aspect = (float)canvas->Width() / (float)canvas->Height();
+    }
+    gfx::Matrix4x4 projection =
+        ConstructInlineProjection((float)fov, aspect, depthNear, depthFar);
+
+    viewerPose =
+        mSession->PooledViewerPose(gfx::Matrix4x4Double(), emulatedPosition);
+    viewerPose->GetEye(0)->Update(gfx::PointDouble3D(), gfx::QuaternionDouble(),
+                                  projection);
+  }
+
+  return viewerPose.forget();
+}
+
+already_AddRefed<XRPose> XRFrame::GetPose(const XRSpace& aSpace,
+                                          const XRSpace& aBaseSpace,
+                                          ErrorResult& aRv) {
+  if (!mActive) {
+    aRv.ThrowInvalidStateError(
+        "GetPose can not be called on an XRFrame that is not active.");
+    return nullptr;
+  }
+
+  if (aSpace.GetSession() != mSession || aBaseSpace.GetSession() != mSession) {
+    aRv.ThrowInvalidStateError(
+        "The XRSpace passed to GetPose must belong to the "
+        "XRSession that GetPose is called on.");
+    return nullptr;
+  }
+
+  // TODO (Bug 1616390) - Validate that poses may be reported:
+  // https://immersive-web.github.io/webxr/#poses-may-be-reported
+  if (aSpace.GetSession()->VisibilityState() != XRVisibilityState::Visible) {
+    aRv.ThrowInvalidStateError(
+        "An XRSpace ’s visibilityState in not 'visible'.");
+    return nullptr;
+  }
+
+  // TODO (Bug 1616393) - Check if poses must be limited:
+  // https://immersive-web.github.io/webxr/#poses-must-be-limited
+
+  const bool emulatedPosition = aSpace.IsPositionEmulated();
+  gfx::Matrix4x4Double base;
+  base.SetRotationFromQuaternion(
+      aBaseSpace.GetEffectiveOriginOrientation().Inverse());
+  base.PreTranslate(-aBaseSpace.GetEffectiveOriginPosition());
+
+  gfx::Matrix4x4Double matrix = aSpace.GetEffectiveOriginTransform() * base;
+
+  RefPtr<XRRigidTransform> transform = new XRRigidTransform(mParent, matrix);
+  RefPtr<XRPose> pose = new XRPose(mParent, transform, emulatedPosition);
+
+  return pose.forget();
+}
+
+void XRFrame::StartAnimationFrame() {
+  mActive = true;
+  mAnimationFrame = true;
+}
+
+void XRFrame::EndAnimationFrame() { mActive = false; }
+
+void XRFrame::StartInputSourceEvent() { mActive = true; }
+
+void XRFrame::EndInputSourceEvent() { mActive = false; }
+
+gfx::Matrix4x4 XRFrame::ConstructInlineProjection(float aFov, float aAspect,
+                                                  float aNear, float aFar) {
+  gfx::Matrix4x4 m;
+  const float depth = aFar - aNear;
+  const float invDepth = 1 / depth;
+  if (aFov == 0) {
+    aFov = 0.5f * M_PI;
+  }
+
+  m._22 = 1.0f / tan(0.5f * aFov);
+  m._11 = -m._22 / aAspect;
+  m._33 = depth * invDepth;
+  m._43 = (-aFar * aNear) * invDepth;
+  m._34 = 1.0f;
+
+  return m;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRFrame.h b/dom/vr/XRFrame.h
new file mode 100644
index 0000000000..3faf2045cd
--- /dev/null
+++ b/dom/vr/XRFrame.h
@@ -0,0 +1,65 @@
+/* -*- 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_XRFrame_h_
+#define mozilla_dom_XRFrame_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRFrameOfReference;
+class XRInputPose;
+class XRInputSource;
+class XRPose;
+class XRReferenceSpace;
+class XRSession;
+class XRSpace;
+class XRViewerPose;
+
+class XRFrame final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(XRFrame)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(XRFrame)
+
+  explicit XRFrame(nsISupports* aParent, XRSession* aXRSession);
+
+  void StartAnimationFrame();
+  void EndAnimationFrame();
+  void StartInputSourceEvent();
+  void EndInputSourceEvent();
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  XRSession* Session();
+  already_AddRefed<XRViewerPose> GetViewerPose(
+      const XRReferenceSpace& aReferenceSpace, ErrorResult& aRv);
+  already_AddRefed<XRPose> GetPose(const XRSpace& aSpace,
+                                   const XRSpace& aBaseSpace, ErrorResult& aRv);
+  gfx::Matrix4x4 ConstructInlineProjection(float aFov, float aAspect,
+                                           float aNear, float aFar);
+
+ protected:
+  virtual ~XRFrame() = default;
+
+  nsCOMPtr<nsISupports> mParent;
+  RefPtr<XRSession> mSession;
+  bool mActive;
+  bool mAnimationFrame;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRFrame_h_
diff --git a/dom/vr/XRInputSource.cpp b/dom/vr/XRInputSource.cpp
new file mode 100644
index 0000000000..c575281252
--- /dev/null
+++ b/dom/vr/XRInputSource.cpp
@@ -0,0 +1,396 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRInputSource.h"
+#include "mozilla/dom/XRInputSourceEvent.h"
+#include "XRNativeOriginViewer.h"
+#include "XRNativeOriginTracker.h"
+#include "XRInputSpace.h"
+#include "VRDisplayClient.h"
+
+#include "mozilla/HoldDropJSObjects.h"
+#include "mozilla/dom/Gamepad.h"
+#include "mozilla/dom/GamepadManager.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(XRInputSource, mParent, mTargetRaySpace,
+                                      mGripSpace, mGamepad)
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(XRInputSource, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(XRInputSource, Release)
+
+// Follow the controller profile ids from
+// https://github.com/immersive-web/webxr-input-profiles.
+nsTArray<nsString> GetInputSourceProfile(gfx::VRControllerType aType) {
+  nsTArray<nsString> profile;
+  nsString id;
+
+  switch (aType) {
+    case gfx::VRControllerType::HTCVive:
+      id.AssignLiteral("htc-vive");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-touchpad");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::HTCViveCosmos:
+      id.AssignLiteral("htc-vive-cosmos");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-thumbstick");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::HTCViveFocus:
+      id.AssignLiteral("htc-vive-focus");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-touchpad");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::HTCViveFocusPlus:
+      id.AssignLiteral("htc-vive-focus-plus");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-touchpad");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::MSMR:
+      id.AssignLiteral("microsoft-mixed-reality");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-touchpad-thumbstick");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::ValveIndex:
+      id.AssignLiteral("valve-index");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-touchpad-thumbstick");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::OculusGo:
+      id.AssignLiteral("oculus-go");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-touchpad");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::OculusTouch:
+      id.AssignLiteral("oculus-touch");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-thumbstick");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::OculusTouch2:
+      id.AssignLiteral("oculus-touch-v2");
+      profile.AppendElement(id);
+      id.AssignLiteral("oculus-touch");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-thumbstick");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::PicoGaze:
+      id.AssignLiteral("pico-gaze");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-button");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::PicoG2:
+      id.AssignLiteral("pico-g2");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-touchpad");
+      profile.AppendElement(id);
+      break;
+    case gfx::VRControllerType::PicoNeo2:
+      id.AssignLiteral("pico-neo2");
+      profile.AppendElement(id);
+      id.AssignLiteral("generic-trigger-squeeze-thumbstick");
+      profile.AppendElement(id);
+      break;
+    default:
+      NS_WARNING("Unsupported XR input source profile.\n");
+      break;
+  }
+  return profile;
+}
+
+XRInputSource::XRInputSource(nsISupports* aParent)
+    : mParent(aParent),
+      mGamepad(nullptr),
+      mIndex(-1),
+      mSelectAction(ActionState::ActionState_Released),
+      mSqueezeAction(ActionState::ActionState_Released) {}
+
+XRInputSource::~XRInputSource() {
+  mTargetRaySpace = nullptr;
+  mGripSpace = nullptr;
+  mGamepad = nullptr;
+  mozilla::DropJSObjects(this);
+}
+
+JSObject* XRInputSource::WrapObject(JSContext* aCx,
+                                    JS::Handle<JSObject*> aGivenProto) {
+  return XRInputSource_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+XRHandedness XRInputSource::Handedness() { return mHandedness; }
+
+XRTargetRayMode XRInputSource::TargetRayMode() { return mTargetRayMode; }
+
+XRSpace* XRInputSource::TargetRaySpace() { return mTargetRaySpace; }
+
+XRSpace* XRInputSource::GetGripSpace() { return mGripSpace; }
+
+void XRInputSource::GetProfiles(nsTArray<nsString>& aResult) {
+  aResult = mProfiles.Clone();
+}
+
+Gamepad* XRInputSource::GetGamepad() { return mGamepad; }
+
+void XRInputSource::Setup(XRSession* aSession, uint32_t aIndex) {
+  MOZ_ASSERT(aSession);
+  gfx::VRDisplayClient* displayClient = aSession->GetDisplayClient();
+  if (!displayClient) {
+    MOZ_ASSERT(displayClient);
+    return;
+  }
+  const gfx::VRDisplayInfo& displayInfo = displayClient->GetDisplayInfo();
+  const gfx::VRControllerState& controllerState =
+      displayInfo.mControllerState[aIndex];
+  MOZ_ASSERT(controllerState.controllerName[0] != '\0');
+
+  mProfiles = GetInputSourceProfile(controllerState.type);
+  mHandedness = XRHandedness::None;
+  switch (controllerState.hand) {
+    case GamepadHand::_empty:
+      mHandedness = XRHandedness::None;
+      break;
+    case GamepadHand::Left:
+      mHandedness = XRHandedness::Left;
+      break;
+    case GamepadHand::Right:
+      mHandedness = XRHandedness::Right;
+      break;
+    default:
+      MOZ_ASSERT(false && "Unknown GamepadHand type.");
+      break;
+  }
+
+  RefPtr<XRNativeOrigin> nativeOriginTargetRay = nullptr;
+  mTargetRayMode = XRTargetRayMode::Tracked_pointer;
+  switch (controllerState.targetRayMode) {
+    case gfx::TargetRayMode::Gaze:
+      mTargetRayMode = XRTargetRayMode::Gaze;
+      nativeOriginTargetRay = new XRNativeOriginViewer(displayClient);
+      break;
+    case gfx::TargetRayMode::TrackedPointer:
+      mTargetRayMode = XRTargetRayMode::Tracked_pointer;
+      // We use weak pointers of poses in XRNativeOriginTracker to sync their
+      // data internally.
+      nativeOriginTargetRay =
+          new XRNativeOriginTracker(&controllerState.targetRayPose);
+      break;
+    case gfx::TargetRayMode::Screen:
+      mTargetRayMode = XRTargetRayMode::Screen;
+      break;
+    default:
+      MOZ_ASSERT(false && "Undefined TargetRayMode type.");
+      break;
+  }
+
+  mTargetRaySpace = new XRInputSpace(aSession->GetParentObject(), aSession,
+                                     nativeOriginTargetRay, aIndex);
+
+  const uint32_t gamepadHandleValue =
+      displayInfo.mDisplayID * gfx::kVRControllerMaxCount + aIndex;
+
+  const GamepadHandle gamepadHandle{gamepadHandleValue, GamepadHandleKind::VR};
+
+  mGamepad =
+      new Gamepad(mParent, NS_ConvertASCIItoUTF16(""), -1, gamepadHandle,
+                  GamepadMappingType::Xr_standard, controllerState.hand,
+                  displayInfo.mDisplayID, controllerState.numButtons,
+                  controllerState.numAxes, controllerState.numHaptics, 0, 0);
+  mIndex = aIndex;
+
+  if (!mGripSpace) {
+    CreateGripSpace(aSession, controllerState);
+  }
+}
+
+void XRInputSource::SetGamepadIsConnected(bool aConnected,
+                                          XRSession* aSession) {
+  mGamepad->SetConnected(aConnected);
+  MOZ_ASSERT(aSession);
+
+  if (!aConnected) {
+    if (mSelectAction != ActionState::ActionState_Released) {
+      DispatchEvent(u"selectend"_ns, aSession);
+      mSelectAction = ActionState::ActionState_Released;
+    }
+    if (mSqueezeAction != ActionState::ActionState_Released) {
+      DispatchEvent(u"squeezeend"_ns, aSession);
+      mSqueezeAction = ActionState::ActionState_Released;
+    }
+  }
+}
+
+void XRInputSource::Update(XRSession* aSession) {
+  MOZ_ASSERT(aSession && mIndex >= 0 && mGamepad);
+
+  gfx::VRDisplayClient* displayClient = aSession->GetDisplayClient();
+  if (!displayClient) {
+    MOZ_ASSERT(displayClient);
+    return;
+  }
+  const gfx::VRDisplayInfo& displayInfo = displayClient->GetDisplayInfo();
+  const gfx::VRControllerState& controllerState =
+      displayInfo.mControllerState[mIndex];
+  MOZ_ASSERT(controllerState.controllerName[0] != '\0');
+
+  // OculusVR and OpenVR controllers need to wait until
+  // update functions to assign GamepadCapabilityFlags::Cap_GripSpacePosition
+  // flag.
+  if (!mGripSpace) {
+    CreateGripSpace(aSession, controllerState);
+  }
+
+  // Update button values.
+  nsTArray<RefPtr<GamepadButton>> buttons;
+  mGamepad->GetButtons(buttons);
+  for (uint32_t i = 0; i < buttons.Length(); ++i) {
+    const bool pressed = controllerState.buttonPressed & (1ULL << i);
+    const bool touched = controllerState.buttonTouched & (1ULL << i);
+
+    if (buttons[i]->Pressed() != pressed || buttons[i]->Touched() != touched ||
+        buttons[i]->Value() != controllerState.triggerValue[i]) {
+      mGamepad->SetButton(i, pressed, touched, controllerState.triggerValue[i]);
+    }
+  }
+  // Update axis values.
+  nsTArray<double> axes;
+  mGamepad->GetAxes(axes);
+  for (uint32_t i = 0; i < axes.Length(); ++i) {
+    if (axes[i] != controllerState.axisValue[i]) {
+      mGamepad->SetAxis(i, controllerState.axisValue[i]);
+    }
+  }
+
+  // We define 0.85f and 0.15f based on our current finding
+  // for better experience, we can adjust these values if we need.
+  const float completeThreshold = 0.90f;
+  const float startThreshold = 0.85f;
+  const float endThreshold = 0.15f;
+  const uint32_t selectIndex = 0;
+  const uint32_t squeezeIndex = 1;
+
+  // Checking selectstart, select, selectend
+  if (buttons.Length() > selectIndex) {
+    if (controllerState.selectActionStartFrameId >
+        controllerState.selectActionStopFrameId) {
+      if (mSelectAction == ActionState::ActionState_Released &&
+          controllerState.triggerValue[selectIndex] > endThreshold) {
+        DispatchEvent(u"selectstart"_ns, aSession);
+        mSelectAction = ActionState::ActionState_Pressing;
+      } else if (mSelectAction == ActionState::ActionState_Pressing &&
+                 controllerState.triggerValue[selectIndex] >
+                     completeThreshold) {
+        mSelectAction = ActionState::ActionState_Pressed;
+      } else if (mSelectAction == ActionState::ActionState_Pressed &&
+                 controllerState.triggerValue[selectIndex] < startThreshold) {
+        DispatchEvent(u"select"_ns, aSession);
+        mSelectAction = ActionState::ActionState_Releasing;
+      } else if (mSelectAction <= ActionState::ActionState_Releasing &&
+                 controllerState.triggerValue[selectIndex] < endThreshold) {
+        // For a select btn which only has pressed and unpressed status.
+        if (mSelectAction == ActionState::ActionState_Pressed) {
+          DispatchEvent(u"select"_ns, aSession);
+        }
+        DispatchEvent(u"selectend"_ns, aSession);
+        mSelectAction = ActionState::ActionState_Released;
+      }
+    } else if (mSelectAction <= ActionState::ActionState_Releasing) {
+      // For a select btn which only has pressed and unpressed status.
+      if (mSelectAction == ActionState::ActionState_Pressed) {
+        DispatchEvent(u"select"_ns, aSession);
+      }
+      DispatchEvent(u"selectend"_ns, aSession);
+      mSelectAction = ActionState::ActionState_Released;
+    }
+  }
+
+  // Checking squeezestart, squeeze, squeezeend
+  if (buttons.Length() > squeezeIndex) {
+    if (controllerState.squeezeActionStartFrameId >
+        controllerState.squeezeActionStopFrameId) {
+      if (mSqueezeAction == ActionState::ActionState_Released &&
+          controllerState.triggerValue[squeezeIndex] > endThreshold) {
+        DispatchEvent(u"squeezestart"_ns, aSession);
+        mSqueezeAction = ActionState::ActionState_Pressing;
+      } else if (mSqueezeAction == ActionState::ActionState_Pressing &&
+                 controllerState.triggerValue[squeezeIndex] >
+                     completeThreshold) {
+        mSqueezeAction = ActionState::ActionState_Pressed;
+      } else if (mSqueezeAction == ActionState::ActionState_Pressed &&
+                 controllerState.triggerValue[squeezeIndex] < startThreshold) {
+        DispatchEvent(u"squeeze"_ns, aSession);
+        mSqueezeAction = ActionState::ActionState_Releasing;
+      } else if (mSqueezeAction <= ActionState::ActionState_Releasing &&
+                 controllerState.triggerValue[squeezeIndex] < endThreshold) {
+        // For a squeeze btn which only has pressed and unpressed status.
+        if (mSqueezeAction == ActionState::ActionState_Pressed) {
+          DispatchEvent(u"squeeze"_ns, aSession);
+        }
+        DispatchEvent(u"squeezeend"_ns, aSession);
+        mSqueezeAction = ActionState::ActionState_Released;
+      }
+    } else if (mSqueezeAction <= ActionState::ActionState_Releasing) {
+      // For a squeeze btn which only has pressed and unpressed status.
+      if (mSqueezeAction == ActionState::ActionState_Pressed) {
+        DispatchEvent(u"squeeze"_ns, aSession);
+      }
+      DispatchEvent(u"squeezeend"_ns, aSession);
+      mSqueezeAction = ActionState::ActionState_Released;
+    }
+  }
+}
+
+int32_t XRInputSource::GetIndex() { return mIndex; }
+
+void XRInputSource::DispatchEvent(const nsAString& aEvent,
+                                  XRSession* aSession) {
+  if (!GetParentObject() || !aSession) {
+    return;
+  }
+  // Create a XRFrame for its callbacks
+  RefPtr<XRFrame> frame = new XRFrame(GetParentObject(), aSession);
+  frame->StartInputSourceEvent();
+
+  XRInputSourceEventInit init;
+  init.mBubbles = false;
+  init.mCancelable = false;
+  init.mFrame = frame;
+  init.mInputSource = this;
+
+  RefPtr<XRInputSourceEvent> event =
+      XRInputSourceEvent::Constructor(aSession, aEvent, init);
+
+  event->SetTrusted(true);
+  aSession->DispatchEvent(*event);
+  frame->EndInputSourceEvent();
+}
+
+void XRInputSource::CreateGripSpace(
+    XRSession* aSession, const gfx::VRControllerState& controllerState) {
+  MOZ_ASSERT(!mGripSpace);
+  MOZ_ASSERT(aSession && mIndex >= 0 && mGamepad);
+  if (mTargetRayMode == XRTargetRayMode::Tracked_pointer &&
+      controllerState.flags & GamepadCapabilityFlags::Cap_GripSpacePosition) {
+    RefPtr<XRNativeOrigin> nativeOriginGrip = nullptr;
+    nativeOriginGrip = new XRNativeOriginTracker(&controllerState.pose);
+    mGripSpace = new XRInputSpace(aSession->GetParentObject(), aSession,
+                                  nativeOriginGrip, mIndex);
+  } else {
+    mGripSpace = nullptr;
+  }
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRInputSource.h b/dom/vr/XRInputSource.h
new file mode 100644
index 0000000000..a44d1aa70d
--- /dev/null
+++ b/dom/vr/XRInputSource.h
@@ -0,0 +1,83 @@
+/* -*- 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_XRInputSource_h_
+#define mozilla_dom_XRInputSource_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace gfx {
+class VRDisplayClient;
+}  // namespace gfx
+namespace dom {
+class Gamepad;
+class XRSpace;
+class XRSession;
+class XRNativeOrigin;
+enum class XRHandedness : uint8_t;
+enum class XRTargetRayMode : uint8_t;
+
+class XRInputSource final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(XRInputSource)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(XRInputSource)
+
+  explicit XRInputSource(nsISupports* aParent);
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  XRHandedness Handedness();
+  XRTargetRayMode TargetRayMode();
+  XRSpace* TargetRaySpace();
+  XRSpace* GetGripSpace();
+  void GetProfiles(nsTArray<nsString>& aResult);
+  Gamepad* GetGamepad();
+  void Setup(XRSession* aSession, uint32_t aIndex);
+  void SetGamepadIsConnected(bool aConnected, XRSession* aSession);
+  void Update(XRSession* aSession);
+  int32_t GetIndex();
+
+ protected:
+  virtual ~XRInputSource();
+
+  nsCOMPtr<nsISupports> mParent;
+
+ private:
+  enum class ActionState : uint8_t {
+    ActionState_Pressing = 0,
+    ActionState_Pressed = 1,
+    ActionState_Releasing = 2,
+    ActionState_Released = 3
+  };
+
+  void CreateGripSpace(XRSession* aSession,
+                       const gfx::VRControllerState& controllerState);
+  void DispatchEvent(const nsAString& aEvent, XRSession* aSession);
+
+  nsTArray<nsString> mProfiles;
+  XRHandedness mHandedness;
+  XRTargetRayMode mTargetRayMode;
+
+  RefPtr<XRSpace> mTargetRaySpace;
+  RefPtr<XRSpace> mGripSpace;
+  RefPtr<Gamepad> mGamepad;
+  int32_t mIndex;
+  ActionState mSelectAction;
+  ActionState mSqueezeAction;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRInputSource_h_
diff --git a/dom/vr/XRInputSourceArray.cpp b/dom/vr/XRInputSourceArray.cpp
new file mode 100644
index 0000000000..acea871097
--- /dev/null
+++ b/dom/vr/XRInputSourceArray.cpp
@@ -0,0 +1,169 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRInputSourceArray.h"
+#include "mozilla/dom/XRSession.h"
+#include "mozilla/dom/XRInputSourcesChangeEvent.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(XRInputSourceArray, mParent,
+                                      mInputSources)
+NS_IMPL_CYCLE_COLLECTING_ADDREF(XRInputSourceArray)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(XRInputSourceArray)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(XRInputSourceArray)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+XRInputSourceArray::XRInputSourceArray(nsISupports* aParent)
+    : mParent(aParent) {}
+
+JSObject* XRInputSourceArray::WrapObject(JSContext* aCx,
+                                         JS::Handle<JSObject*> aGivenProto) {
+  return XRInputSourceArray_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+void XRInputSourceArray::Update(XRSession* aSession) {
+  MOZ_ASSERT(aSession);
+
+  gfx::VRDisplayClient* displayClient = aSession->GetDisplayClient();
+  if (!displayClient) {
+    return;
+  }
+
+  XRInputSourcesChangeEventInit addInit;
+  nsTArray<RefPtr<XRInputSource>> removedInputs;
+  if (NS_WARN_IF(!addInit.mAdded.SetCapacity(gfx::kVRControllerMaxCount,
+                                             mozilla::fallible))) {
+    MOZ_ASSERT(false,
+               "'add' sequence in XRInputSourcesChangeEventInit SetCapacity() "
+               "failed.");
+    return;
+  }
+
+  for (int32_t i = 0; i < gfx::kVRControllerMaxCount; ++i) {
+    const gfx::VRControllerState& controllerState =
+        displayClient->GetDisplayInfo().mControllerState[i];
+    if (controllerState.controllerName[0] == '\0') {
+      // Checking if exising controllers need to be removed.
+      for (auto& input : mInputSources) {
+        if (input->GetIndex() == i) {
+          removedInputs.AppendElement(input);
+          break;
+        }
+      }
+      continue;
+    }
+
+    bool found = false;
+    RefPtr<XRInputSource> inputSource = nullptr;
+    for (auto& input : mInputSources) {
+      if (input->GetIndex() == i) {
+        found = true;
+        inputSource = input;
+        break;
+      }
+    }
+    // Checking if it is added before.
+    if (!found &&
+        (controllerState.numButtons > 0 || controllerState.numAxes > 0)) {
+      inputSource = new XRInputSource(mParent);
+      inputSource->Setup(aSession, i);
+      mInputSources.AppendElement(inputSource);
+
+      addInit.mBubbles = false;
+      addInit.mCancelable = false;
+      addInit.mSession = aSession;
+      if (!addInit.mAdded.AppendElement(*inputSource, mozilla::fallible)) {
+        MOZ_ASSERT(false,
+                   "'add' sequence in XRInputSourcesChangeEventInit "
+                   "AppendElement() failed, it might be due to the"
+                   "wrong size when SetCapacity().");
+      }
+    }
+    // If added, updating the current controller states.
+    if (inputSource) {
+      inputSource->Update(aSession);
+    }
+  }
+
+  // Send `inputsourceschange` for new controllers.
+  if (addInit.mAdded.Length()) {
+    RefPtr<XRInputSourcesChangeEvent> event =
+        XRInputSourcesChangeEvent::Constructor(
+            aSession, u"inputsourceschange"_ns, addInit);
+
+    event->SetTrusted(true);
+    aSession->DispatchEvent(*event);
+  }
+
+  // If there's a controller is removed, dispatch `inputsourceschange`.
+  if (removedInputs.Length()) {
+    DispatchInputSourceRemovedEvent(removedInputs, aSession);
+  }
+  for (auto& input : removedInputs) {
+    mInputSources.RemoveElement(input);
+  }
+}
+
+void XRInputSourceArray::DispatchInputSourceRemovedEvent(
+    const nsTArray<RefPtr<XRInputSource>>& aInputs, XRSession* aSession) {
+  if (!aSession) {
+    return;
+  }
+
+  XRInputSourcesChangeEventInit init;
+  if (NS_WARN_IF(
+          !init.mRemoved.SetCapacity(aInputs.Length(), mozilla::fallible))) {
+    MOZ_ASSERT(false,
+               "'removed' sequence in XRInputSourcesChangeEventInit "
+               "SetCapacity() failed.");
+    return;
+  }
+  for (const auto& input : aInputs) {
+    input->SetGamepadIsConnected(false, aSession);
+    init.mBubbles = false;
+    init.mCancelable = false;
+    init.mSession = aSession;
+    if (!init.mRemoved.AppendElement(*input, mozilla::fallible)) {
+      MOZ_ASSERT(false,
+                 "'removed' sequence in XRInputSourcesChangeEventInit "
+                 "AppendElement() failed, it might be due to the"
+                 "wrong size when SetCapacity().");
+    }
+  }
+
+  if (init.mRemoved.Length()) {
+    RefPtr<XRInputSourcesChangeEvent> event =
+        XRInputSourcesChangeEvent::Constructor(aSession,
+                                               u"inputsourceschange"_ns, init);
+
+    event->SetTrusted(true);
+    aSession->DispatchEvent(*event);
+  }
+}
+
+void XRInputSourceArray::Clear(XRSession* aSession) {
+  DispatchInputSourceRemovedEvent(mInputSources, aSession);
+  mInputSources.Clear();
+}
+
+uint32_t XRInputSourceArray::Length() { return mInputSources.Length(); }
+
+XRInputSource* XRInputSourceArray::IndexedGetter(uint32_t aIndex,
+                                                 bool& aFound) {
+  aFound = aIndex < mInputSources.Length();
+  if (!aFound) {
+    return nullptr;
+  }
+  return mInputSources[aIndex];
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRInputSourceArray.h b/dom/vr/XRInputSourceArray.h
new file mode 100644
index 0000000000..cbd70af688
--- /dev/null
+++ b/dom/vr/XRInputSourceArray.h
@@ -0,0 +1,55 @@
+/* -*- 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_XRInputSourceArray_h_
+#define mozilla_dom_XRInputSourceArray_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace gfx {
+struct VRControllerState;
+}
+namespace dom {
+class XRInputSource;
+
+class XRInputSourceArray final : public nsISupports, public nsWrapperCache {
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(XRInputSourceArray)
+
+  explicit XRInputSourceArray(nsISupports* aParent);
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  XRInputSource* IndexedGetter(uint32_t aIndex, bool& aFound);
+  uint32_t Length();
+  void Setup(XRSession* aSession, RefPtr<gfx::VRDisplayClient> aDisplayClient);
+  void Update(XRSession* aSession);
+  void Clear(XRSession* aSession);
+
+ protected:
+  virtual ~XRInputSourceArray() = default;
+
+ private:
+  void DispatchInputSourceRemovedEvent(
+      const nsTArray<RefPtr<XRInputSource>>& aInputs, XRSession* aSession);
+
+  nsCOMPtr<nsISupports> mParent;
+  nsTArray<RefPtr<XRInputSource>> mInputSources;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRInputSourceArray_h_
diff --git a/dom/vr/XRInputSpace.cpp b/dom/vr/XRInputSpace.cpp
new file mode 100644
index 0000000000..548628a079
--- /dev/null
+++ b/dom/vr/XRInputSpace.cpp
@@ -0,0 +1,36 @@
+/* -*- 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/. */
+
+#include "XRInputSpace.h"
+#include "VRDisplayClient.h"
+#include "mozilla/dom/GamepadPoseState.h"
+
+namespace mozilla {
+namespace dom {
+
+XRInputSpace::XRInputSpace(nsIGlobalObject* aParent, XRSession* aSession,
+                           XRNativeOrigin* aNativeOrigin,
+                           int32_t aControllerIndex)
+    : XRSpace(aParent, aSession, aNativeOrigin), mIndex(aControllerIndex) {}
+
+bool XRInputSpace::IsPositionEmulated() const {
+  gfx::VRDisplayClient* display = mSession->GetDisplayClient();
+  if (!display) {
+    // When there are no sensors, the position is considered emulated.
+    return true;
+  }
+  const gfx::VRDisplayInfo& displayInfo = display->GetDisplayInfo();
+  const gfx::VRControllerState& controllerState =
+      displayInfo.mControllerState[mIndex];
+  MOZ_ASSERT(controllerState.controllerName[0] != '\0');
+
+  return (
+      (controllerState.flags & GamepadCapabilityFlags::Cap_PositionEmulated) !=
+      GamepadCapabilityFlags::Cap_None);
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRInputSpace.h b/dom/vr/XRInputSpace.h
new file mode 100644
index 0000000000..2c11ac88ed
--- /dev/null
+++ b/dom/vr/XRInputSpace.h
@@ -0,0 +1,34 @@
+/* -*- 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_XRInputSpace_h_
+#define mozilla_dom_XRInputSpace_h_
+
+#include "XRInputSpace.h"
+#include "mozilla/dom/XRSpace.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRInputSpace : public XRSpace {
+ public:
+  explicit XRInputSpace(nsIGlobalObject* aParent, XRSession* aSession,
+                        XRNativeOrigin* aNativeOrigin,
+                        int32_t aControllerIndex);
+
+  virtual bool IsPositionEmulated() const override;
+
+ protected:
+  virtual ~XRInputSpace() = default;
+
+ private:
+  int32_t mIndex;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRInputSpace_h_
diff --git a/dom/vr/XRNativeOrigin.h b/dom/vr/XRNativeOrigin.h
new file mode 100644
index 0000000000..fa8747f28b
--- /dev/null
+++ b/dom/vr/XRNativeOrigin.h
@@ -0,0 +1,34 @@
+/* -*- 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_XRNativeOrigin_h_
+#define mozilla_dom_XRNativeOrigin_h_
+
+#include "gfxVR.h"
+#include "mozilla/RefPtr.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRNativeOrigin {
+ public:
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+  XRNativeOrigin() = default;
+
+  virtual gfx::PointDouble3D GetPosition() = 0;
+  virtual gfx::QuaternionDouble GetOrientation() {
+    static const gfx::QuaternionDouble orientation;
+    return orientation;
+  }
+
+ protected:
+  virtual ~XRNativeOrigin() = default;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRNativeOrigin_h_
diff --git a/dom/vr/XRNativeOriginFixed.cpp b/dom/vr/XRNativeOriginFixed.cpp
new file mode 100644
index 0000000000..941177e275
--- /dev/null
+++ b/dom/vr/XRNativeOriginFixed.cpp
@@ -0,0 +1,18 @@
+/* -*- 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/. */
+
+#include "XRNativeOriginFixed.h"
+
+namespace mozilla {
+namespace dom {
+
+XRNativeOriginFixed::XRNativeOriginFixed(const gfx::PointDouble3D& aPosition)
+    : mPosition(aPosition) {}
+
+gfx::PointDouble3D XRNativeOriginFixed::GetPosition() { return mPosition; }
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRNativeOriginFixed.h b/dom/vr/XRNativeOriginFixed.h
new file mode 100644
index 0000000000..8456e37dee
--- /dev/null
+++ b/dom/vr/XRNativeOriginFixed.h
@@ -0,0 +1,32 @@
+/* -*- 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_XRNativeOriginFixed_h_
+#define mozilla_dom_XRNativeOriginFixed_h_
+
+#include "gfxVR.h"
+#include "XRNativeOrigin.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRNativeOriginFixed : public XRNativeOrigin {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(XRNativeOriginFixed, override)
+  explicit XRNativeOriginFixed(const gfx::PointDouble3D& aPosition);
+
+  gfx::PointDouble3D GetPosition() override;
+
+ private:
+  ~XRNativeOriginFixed() = default;
+
+  gfx::PointDouble3D mPosition;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRNativeOriginFixed_h_
diff --git a/dom/vr/XRNativeOriginLocal.cpp b/dom/vr/XRNativeOriginLocal.cpp
new file mode 100644
index 0000000000..578dcffbde
--- /dev/null
+++ b/dom/vr/XRNativeOriginLocal.cpp
@@ -0,0 +1,36 @@
+/* -*- 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/. */
+
+#include "XRNativeOriginLocal.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+XRNativeOriginLocal::XRNativeOriginLocal(gfx::VRDisplayClient* aDisplay)
+    : mDisplay(aDisplay), mInitialPositionValid(false) {
+  MOZ_ASSERT(aDisplay);
+}
+
+gfx::PointDouble3D XRNativeOriginLocal::GetPosition() {
+  // Keep returning {0,0,0} until a position can be found
+  if (!mInitialPositionValid) {
+    const gfx::VRHMDSensorState& sensorState = mDisplay->GetSensorState();
+    gfx::PointDouble3D origin;
+    if (sensorState.flags & gfx::VRDisplayCapabilityFlags::Cap_Position ||
+        sensorState.flags &
+            gfx::VRDisplayCapabilityFlags::Cap_PositionEmulated) {
+      mInitialPosition.x = sensorState.pose.position[0];
+      mInitialPosition.y = sensorState.pose.position[1];
+      mInitialPosition.z = sensorState.pose.position[2];
+      mInitialPositionValid = true;
+    }
+  }
+  return mInitialPosition;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRNativeOriginLocal.h b/dom/vr/XRNativeOriginLocal.h
new file mode 100644
index 0000000000..882f02c96d
--- /dev/null
+++ b/dom/vr/XRNativeOriginLocal.h
@@ -0,0 +1,36 @@
+/* -*- 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_XRNativeOriginLocal_h_
+#define mozilla_dom_XRNativeOriginLocal_h_
+
+#include "gfxVR.h"
+#include "XRNativeOrigin.h"
+
+namespace mozilla {
+namespace gfx {
+class VRDisplayClient;
+}
+namespace dom {
+
+class XRNativeOriginLocal : public XRNativeOrigin {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(XRNativeOriginLocal, override)
+  explicit XRNativeOriginLocal(gfx::VRDisplayClient* aDisplay);
+
+  gfx::PointDouble3D GetPosition() override;
+
+ private:
+  ~XRNativeOriginLocal() = default;
+  RefPtr<gfx::VRDisplayClient> mDisplay;
+  gfx::PointDouble3D mInitialPosition;
+  bool mInitialPositionValid;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRNativeOriginLocal_h_
diff --git a/dom/vr/XRNativeOriginLocalFloor.cpp b/dom/vr/XRNativeOriginLocalFloor.cpp
new file mode 100644
index 0000000000..3d4c3c4ace
--- /dev/null
+++ b/dom/vr/XRNativeOriginLocalFloor.cpp
@@ -0,0 +1,44 @@
+/* -*- 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/. */
+
+#include "XRNativeOriginLocalFloor.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+XRNativeOriginLocalFloor::XRNativeOriginLocalFloor(
+    gfx::VRDisplayClient* aDisplay)
+    : mDisplay(aDisplay), mInitialPositionValid(false) {
+  MOZ_ASSERT(aDisplay);
+
+  // To avoid fingerprinting, we offset the floor height by 5cm.
+  // This will always result in the floor being lower than the
+  // real floor in order to avoid breaking content that expects
+  // you to pick objects up off the floor.
+  //
+  // TODO (Bug 1616394) - Convert this constant to a pref.
+  const double kFloorFuzz = 0.05f;  // Meters
+  mFloorRandom = double(rand()) / double(RAND_MAX) * kFloorFuzz;
+}
+
+gfx::PointDouble3D XRNativeOriginLocalFloor::GetPosition() {
+  // Keep returning {0,-fuzz,0} until a position can be found
+  const auto standing =
+      mDisplay->GetDisplayInfo().GetSittingToStandingTransform();
+  if (!mInitialPositionValid || standing != mStandingTransform) {
+    const gfx::VRHMDSensorState& sensorState = mDisplay->GetSensorState();
+    mInitialPosition.x = sensorState.pose.position[0];
+    mInitialPosition.y = -mFloorRandom - standing._42;
+    mInitialPosition.z = sensorState.pose.position[2];
+    mInitialPositionValid = true;
+    mStandingTransform = standing;
+  }
+  return mInitialPosition;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRNativeOriginLocalFloor.h b/dom/vr/XRNativeOriginLocalFloor.h
new file mode 100644
index 0000000000..77b9ce28f3
--- /dev/null
+++ b/dom/vr/XRNativeOriginLocalFloor.h
@@ -0,0 +1,38 @@
+/* -*- 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_XRNativeOriginLocalFloor_h_
+#define mozilla_dom_XRNativeOriginLocalFloor_h_
+
+#include "gfxVR.h"
+#include "XRNativeOrigin.h"
+
+namespace mozilla {
+namespace gfx {
+class VRDisplayClient;
+}
+namespace dom {
+
+class XRNativeOriginLocalFloor : public XRNativeOrigin {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(XRNativeOriginLocalFloor, override)
+  explicit XRNativeOriginLocalFloor(gfx::VRDisplayClient* aDisplay);
+
+  gfx::PointDouble3D GetPosition() override;
+
+ private:
+  ~XRNativeOriginLocalFloor() = default;
+  RefPtr<gfx::VRDisplayClient> mDisplay;
+  gfx::PointDouble3D mInitialPosition;
+  gfx::Matrix4x4 mStandingTransform;
+  bool mInitialPositionValid;
+  double mFloorRandom;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRNativeOriginLocalFloor_h_
diff --git a/dom/vr/XRNativeOriginTracker.cpp b/dom/vr/XRNativeOriginTracker.cpp
new file mode 100644
index 0000000000..888328a344
--- /dev/null
+++ b/dom/vr/XRNativeOriginTracker.cpp
@@ -0,0 +1,32 @@
+/* -*- 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/. */
+
+#include "XRNativeOriginTracker.h"
+
+namespace mozilla {
+namespace dom {
+
+XRNativeOriginTracker::XRNativeOriginTracker(const gfx::VRPose* aPose)
+    : mPose(aPose) {
+  MOZ_ASSERT(aPose);
+}
+
+gfx::PointDouble3D XRNativeOriginTracker::GetPosition() {
+  MOZ_ASSERT(mPose);
+  return gfx::PointDouble3D(mPose->position[0], mPose->position[1],
+                            mPose->position[2]);
+}
+
+gfx::QuaternionDouble XRNativeOriginTracker::GetOrientation() {
+  MOZ_ASSERT(mPose);
+  gfx::QuaternionDouble orientation(
+      mPose->orientation[0], mPose->orientation[1], mPose->orientation[2],
+      mPose->orientation[3]);
+  return orientation;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRNativeOriginTracker.h b/dom/vr/XRNativeOriginTracker.h
new file mode 100644
index 0000000000..81d27568e7
--- /dev/null
+++ b/dom/vr/XRNativeOriginTracker.h
@@ -0,0 +1,32 @@
+/* -*- 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_XRNativeOriginTracker_h_
+#define mozilla_dom_XRNativeOriginTracker_h_
+
+#include "gfxVR.h"
+#include "XRNativeOrigin.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRNativeOriginTracker : public XRNativeOrigin {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(XRNativeOriginTracker, override)
+  explicit XRNativeOriginTracker(const gfx::VRPose* aPose);
+
+  gfx::PointDouble3D GetPosition() override;
+  gfx::QuaternionDouble GetOrientation() override;
+
+ private:
+  ~XRNativeOriginTracker() = default;
+  const gfx::VRPose* mPose;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRNativeOriginTracker_h_
diff --git a/dom/vr/XRNativeOriginViewer.cpp b/dom/vr/XRNativeOriginViewer.cpp
new file mode 100644
index 0000000000..c0f85844b1
--- /dev/null
+++ b/dom/vr/XRNativeOriginViewer.cpp
@@ -0,0 +1,33 @@
+/* -*- 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/. */
+
+#include "XRNativeOriginViewer.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+XRNativeOriginViewer::XRNativeOriginViewer(gfx::VRDisplayClient* aDisplay)
+    : mDisplay(aDisplay) {
+  MOZ_ASSERT(aDisplay);
+}
+
+gfx::PointDouble3D XRNativeOriginViewer::GetPosition() {
+  const gfx::VRHMDSensorState& sensorState = mDisplay->GetSensorState();
+  return gfx::PointDouble3D(sensorState.pose.position[0],
+                            sensorState.pose.position[1],
+                            sensorState.pose.position[2]);
+}
+
+gfx::QuaternionDouble XRNativeOriginViewer::GetOrientation() {
+  const gfx::VRHMDSensorState& sensorState = mDisplay->GetSensorState();
+  return gfx::QuaternionDouble(
+      sensorState.pose.orientation[0], sensorState.pose.orientation[1],
+      sensorState.pose.orientation[2], sensorState.pose.orientation[3]);
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRNativeOriginViewer.h b/dom/vr/XRNativeOriginViewer.h
new file mode 100644
index 0000000000..6178ae66ea
--- /dev/null
+++ b/dom/vr/XRNativeOriginViewer.h
@@ -0,0 +1,35 @@
+/* -*- 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_XRNativeOriginViewer_h_
+#define mozilla_dom_XRNativeOriginViewer_h_
+
+#include "gfxVR.h"
+#include "XRNativeOrigin.h"
+
+namespace mozilla {
+namespace gfx {
+class VRDisplayClient;
+}
+namespace dom {
+
+class XRNativeOriginViewer : public XRNativeOrigin {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(XRNativeOriginViewer, override)
+  explicit XRNativeOriginViewer(gfx::VRDisplayClient* aDisplay);
+
+  gfx::PointDouble3D GetPosition() override;
+  gfx::QuaternionDouble GetOrientation() override;
+
+ private:
+  ~XRNativeOriginViewer() = default;
+  RefPtr<gfx::VRDisplayClient> mDisplay;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRNativeOriginViewer_h_
diff --git a/dom/vr/XRPermissionRequest.cpp b/dom/vr/XRPermissionRequest.cpp
new file mode 100644
index 0000000000..96315730c6
--- /dev/null
+++ b/dom/vr/XRPermissionRequest.cpp
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "XRPermissionRequest.h"
+#include "nsGlobalWindowInner.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/Preferences.h"
+#include "nsContentUtils.h"
+
+namespace mozilla {
+namespace dom {
+
+//-------------------------------------------------
+// XR Permission Requests
+//-------------------------------------------------
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(XRPermissionRequest,
+                                               ContentPermissionRequestBase)
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(XRPermissionRequest,
+                                   ContentPermissionRequestBase)
+
+XRPermissionRequest::XRPermissionRequest(nsPIDOMWindowInner* aWindow,
+                                         uint64_t aWindowId)
+    : ContentPermissionRequestBase(aWindow->GetDoc()->NodePrincipal(), aWindow,
+                                   "dom.vr"_ns, "xr"_ns),
+      mWindowId(aWindowId) {
+  MOZ_ASSERT(aWindow);
+  MOZ_ASSERT(aWindow->GetDoc());
+  mPrincipal = aWindow->GetDoc()->NodePrincipal();
+  MOZ_ASSERT(mPrincipal);
+}
+
+NS_IMETHODIMP
+XRPermissionRequest::Cancel() {
+  nsGlobalWindowInner* window =
+      nsGlobalWindowInner::GetInnerWindowWithId(mWindowId);
+  if (!window) {
+    return NS_OK;
+  }
+  window->OnXRPermissionRequestCancel();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+XRPermissionRequest::Allow(JS::HandleValue aChoices) {
+  MOZ_ASSERT(aChoices.isUndefined());
+  nsGlobalWindowInner* window =
+      nsGlobalWindowInner::GetInnerWindowWithId(mWindowId);
+  if (!window) {
+    return NS_OK;
+  }
+  window->OnXRPermissionRequestAllow();
+  return NS_OK;
+}
+
+nsresult XRPermissionRequest::Start() {
+  MOZ_ASSERT(NS_IsMainThread());
+  if (!CheckPermissionDelegate()) {
+    return Cancel();
+  }
+  PromptResult pr = CheckPromptPrefs();
+  if (pr == PromptResult::Granted) {
+    return Allow(JS::UndefinedHandleValue);
+  }
+  if (pr == PromptResult::Denied) {
+    return Cancel();
+  }
+
+  return nsContentPermissionUtils::AskPermission(this, mWindow);
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRPermissionRequest.h b/dom/vr/XRPermissionRequest.h
new file mode 100644
index 0000000000..6ea2301bf2
--- /dev/null
+++ b/dom/vr/XRPermissionRequest.h
@@ -0,0 +1,41 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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_XRPermissionRequest_h_
+#define mozilla_dom_XRPermissionRequest_h_
+
+#include "mozilla/dom/Promise.h"
+#include "nsContentPermissionHelper.h"
+#include "nsISupports.h"
+
+namespace mozilla {
+namespace dom {
+
+/**
+ * Handles permission dialog management when requesting XR device access.
+ */
+class XRPermissionRequest final : public ContentPermissionRequestBase {
+ public:
+  XRPermissionRequest(nsPIDOMWindowInner* aWindow, uint64_t aWindowId);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XRPermissionRequest,
+                                           ContentPermissionRequestBase)
+  // nsIContentPermissionRequest
+  NS_IMETHOD Cancel(void) override;
+  NS_IMETHOD Allow(JS::HandleValue choices) override;
+  nsresult Start();
+
+ private:
+  ~XRPermissionRequest() = default;
+
+  uint64_t mWindowId;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XR_h_
diff --git a/dom/vr/XRPose.cpp b/dom/vr/XRPose.cpp
new file mode 100644
index 0000000000..2b32cd66c2
--- /dev/null
+++ b/dom/vr/XRPose.cpp
@@ -0,0 +1,42 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRPose.h"
+#include "mozilla/dom/XRRigidTransform.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(XRPose, mParent, mTransform)
+NS_IMPL_CYCLE_COLLECTING_ADDREF(XRPose)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(XRPose)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(XRPose)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+XRPose::XRPose(nsISupports* aParent, XRRigidTransform* aTransform,
+               bool aEmulatedPosition)
+    : mParent(aParent),
+      mTransform(aTransform),
+      mEmulatedPosition(aEmulatedPosition) {}
+
+JSObject* XRPose::WrapObject(JSContext* aCx,
+                             JS::Handle<JSObject*> aGivenProto) {
+  return XRPose_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+void XRPose::SetEmulatedPosition(bool aEmulated) {
+  mEmulatedPosition = aEmulated;
+}
+
+XRRigidTransform* XRPose::Transform() { return mTransform; }
+
+bool XRPose::EmulatedPosition() const { return mEmulatedPosition; }
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRPose.h b/dom/vr/XRPose.h
new file mode 100644
index 0000000000..0f189e4d3f
--- /dev/null
+++ b/dom/vr/XRPose.h
@@ -0,0 +1,50 @@
+/* -*- 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_XRPose_h_
+#define mozilla_dom_XRPose_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "mozilla/dom/XRRigidTransform.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRRigidTransform;
+class XRView;
+
+class XRPose : public nsISupports, public nsWrapperCache {
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(XRPose)
+
+  explicit XRPose(nsISupports* aParent, XRRigidTransform* aTransform,
+                  bool aEmulatedPosition);
+  void SetEmulatedPosition(bool aEmulated);
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  XRRigidTransform* Transform();
+  bool EmulatedPosition() const;
+
+ protected:
+  virtual ~XRPose() = default;
+  nsCOMPtr<nsISupports> mParent;
+  RefPtr<XRRigidTransform> mTransform;
+  bool mEmulatedPosition;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRPose_h_
diff --git a/dom/vr/XRReferenceSpace.cpp b/dom/vr/XRReferenceSpace.cpp
new file mode 100644
index 0000000000..7615038488
--- /dev/null
+++ b/dom/vr/XRReferenceSpace.cpp
@@ -0,0 +1,47 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRReferenceSpace.h"
+#include "mozilla/dom/XRRigidTransform.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+XRReferenceSpace::XRReferenceSpace(nsIGlobalObject* aParent,
+                                   XRSession* aSession,
+                                   XRNativeOrigin* aNativeOrigin,
+                                   XRReferenceSpaceType aType)
+    : XRSpace(aParent, aSession, aNativeOrigin), mType(aType) {}
+
+already_AddRefed<XRReferenceSpace> XRReferenceSpace::GetOffsetReferenceSpace(
+    const XRRigidTransform& aOriginOffset) {
+  RefPtr<XRReferenceSpace> offsetReferenceSpace =
+      new XRReferenceSpace(GetParentObject(), mSession, mNativeOrigin, mType);
+
+  // https://immersive-web.github.io/webxr/#multiply-transforms
+  // An XRRigidTransform is essentially a rotation followed by a translation
+  gfx::QuaternionDouble otherOrientation = aOriginOffset.RawOrientation();
+  // The resulting rotation is the two combined
+  offsetReferenceSpace->mOriginOffsetOrientation =
+      mOriginOffsetOrientation * otherOrientation;
+  // We first apply the rotation of aOriginOffset to
+  // mOriginOffsetPosition offset, then translate by the offset of
+  // aOriginOffset
+  offsetReferenceSpace->mOriginOffsetPosition =
+      otherOrientation.RotatePoint(mOriginOffsetPosition) +
+      aOriginOffset.RawPosition();
+
+  return offsetReferenceSpace.forget();
+}
+
+JSObject* XRReferenceSpace::WrapObject(JSContext* aCx,
+                                       JS::Handle<JSObject*> aGivenProto) {
+  return XRReferenceSpace_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRReferenceSpace.h b/dom/vr/XRReferenceSpace.h
new file mode 100644
index 0000000000..f5054075ca
--- /dev/null
+++ b/dom/vr/XRReferenceSpace.h
@@ -0,0 +1,49 @@
+/* -*- 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_XRReferenceSpace_h_
+#define mozilla_dom_XRReferenceSpace_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "mozilla/dom/XRSpace.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+enum class XRReferenceSpaceType : uint8_t;
+class XRRigidTransform;
+class XRSession;
+
+class XRReferenceSpace : public XRSpace {
+ public:
+  explicit XRReferenceSpace(nsIGlobalObject* aParent, XRSession* aSession,
+                            XRNativeOrigin* aNativeOrigin,
+                            XRReferenceSpaceType aType);
+
+  // WebIDL Boilerplate
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  virtual already_AddRefed<XRReferenceSpace> GetOffsetReferenceSpace(
+      const XRRigidTransform& aOriginOffset);
+
+  // TODO (Bug 1611309): Implement XRReferenceSpace reset events
+  // https://immersive-web.github.io/webxr/#eventdef-xrreferencespace-reset
+  IMPL_EVENT_HANDLER(reset);
+
+ protected:
+  virtual ~XRReferenceSpace() = default;
+  XRReferenceSpaceType mType;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRReferenceSpace_h_
diff --git a/dom/vr/XRRenderState.cpp b/dom/vr/XRRenderState.cpp
new file mode 100644
index 0000000000..bb502ec7ac
--- /dev/null
+++ b/dom/vr/XRRenderState.cpp
@@ -0,0 +1,94 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRRenderState.h"
+#include "VRLayerChild.h"
+#include "nsIObserverService.h"
+#include "nsISupportsPrimitives.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(XRRenderState, mParent, mSession,
+                                      mBaseLayer, mOutputCanvas)
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(XRRenderState, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(XRRenderState, Release)
+
+XRRenderState::XRRenderState(nsISupports* aParent, XRSession* aSession)
+    : mParent(aParent),
+      mSession(aSession),
+      mDepthNear(0.1f),
+      mDepthFar(1000.0f),
+      mCompositionDisabled(false) {
+  if (!mSession->IsImmersive()) {
+    mInlineVerticalFieldOfView.SetValue(M_PI * 0.5f);
+  }
+}
+
+XRRenderState::XRRenderState(const XRRenderState& aOther)
+    : mParent(aOther.mParent),
+      mSession(aOther.mSession),
+      mBaseLayer(aOther.mBaseLayer),
+      mDepthNear(aOther.mDepthNear),
+      mDepthFar(aOther.mDepthFar),
+      mInlineVerticalFieldOfView(aOther.mInlineVerticalFieldOfView),
+      mOutputCanvas(aOther.mOutputCanvas),
+      mCompositionDisabled(aOther.mCompositionDisabled) {}
+
+JSObject* XRRenderState::WrapObject(JSContext* aCx,
+                                    JS::Handle<JSObject*> aGivenProto) {
+  return XRRenderState_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+double XRRenderState::DepthNear() { return mDepthNear; }
+
+double XRRenderState::DepthFar() { return mDepthFar; }
+
+Nullable<double> XRRenderState::GetInlineVerticalFieldOfView() {
+  return mInlineVerticalFieldOfView;
+}
+
+void XRRenderState::SetDepthNear(double aDepthNear) { mDepthNear = aDepthNear; }
+
+void XRRenderState::SetDepthFar(double aDepthFar) { mDepthFar = aDepthFar; }
+
+void XRRenderState::SetInlineVerticalFieldOfView(
+    double aInlineVerticalFieldOfView) {
+  mInlineVerticalFieldOfView.SetValue(aInlineVerticalFieldOfView);
+}
+
+XRWebGLLayer* XRRenderState::GetBaseLayer() { return mBaseLayer; }
+
+void XRRenderState::SetBaseLayer(XRWebGLLayer* aBaseLayer) {
+  mBaseLayer = aBaseLayer;
+}
+
+void XRRenderState::SetOutputCanvas(HTMLCanvasElement* aCanvas) {
+  mOutputCanvas = aCanvas;
+}
+
+HTMLCanvasElement* XRRenderState::GetOutputCanvas() const {
+  return mOutputCanvas;
+}
+
+void XRRenderState::SetCompositionDisabled(bool aCompositionDisabled) {
+  mCompositionDisabled = aCompositionDisabled;
+}
+
+bool XRRenderState::IsCompositionDisabled() const {
+  return mCompositionDisabled;
+}
+
+void XRRenderState::SessionEnded() {
+  if (mBaseLayer) {
+    mBaseLayer->SessionEnded();
+    mBaseLayer = nullptr;
+  }
+  mOutputCanvas = nullptr;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRRenderState.h b/dom/vr/XRRenderState.h
new file mode 100644
index 0000000000..da7127d442
--- /dev/null
+++ b/dom/vr/XRRenderState.h
@@ -0,0 +1,67 @@
+/* -*- 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_XRRenderState_h_
+#define mozilla_dom_XRRenderState_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+class XRWebGLLayer;
+
+class XRRenderState final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(XRRenderState)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(XRRenderState)
+
+  explicit XRRenderState(nsISupports* aParent, XRSession* aSession);
+  explicit XRRenderState(const XRRenderState& aOther);
+
+  void SetDepthNear(double aDepthNear);
+  void SetDepthFar(double aDepthFar);
+  void SetInlineVerticalFieldOfView(double aInlineVerticalFieldOfView);
+  void SetBaseLayer(XRWebGLLayer* aBaseLayer);
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  double DepthNear();
+  double DepthFar();
+  Nullable<double> GetInlineVerticalFieldOfView();
+  XRWebGLLayer* GetBaseLayer();
+
+  // Non-WebIDL Members
+  void SetOutputCanvas(HTMLCanvasElement* aCanvas);
+  HTMLCanvasElement* GetOutputCanvas() const;
+  void SetCompositionDisabled(bool aCompositionDisabled);
+  bool IsCompositionDisabled() const;
+  void SessionEnded();
+
+ protected:
+  virtual ~XRRenderState() = default;
+  nsCOMPtr<nsISupports> mParent;
+  RefPtr<XRSession> mSession;
+  RefPtr<XRWebGLLayer> mBaseLayer;
+  double mDepthNear;
+  double mDepthFar;
+  Nullable<double> mInlineVerticalFieldOfView;
+  // https://immersive-web.github.io/webxr/#xrrenderstate-output-canvas
+  RefPtr<HTMLCanvasElement> mOutputCanvas;
+  // https://immersive-web.github.io/webxr/#xrrenderstate-composition-disabled
+  bool mCompositionDisabled;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRRenderState_h_
diff --git a/dom/vr/XRRigidTransform.cpp b/dom/vr/XRRigidTransform.cpp
new file mode 100644
index 0000000000..e45d01a788
--- /dev/null
+++ b/dom/vr/XRRigidTransform.cpp
@@ -0,0 +1,187 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRRigidTransform.h"
+#include "mozilla/dom/DOMPoint.h"
+#include "mozilla/dom/Pose.h"
+#include "mozilla/dom/DOMPointBinding.h"
+#include "mozilla/HoldDropJSObjects.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRRigidTransform)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(XRRigidTransform)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent, mPosition, mOrientation, mInverse)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  tmp->mMatrixArray = nullptr;
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(XRRigidTransform)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent, mPosition, mOrientation, mInverse)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(XRRigidTransform)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mMatrixArray)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(XRRigidTransform, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(XRRigidTransform, Release)
+
+XRRigidTransform::XRRigidTransform(nsISupports* aParent,
+                                   const gfx::PointDouble3D& aPosition,
+                                   const gfx::QuaternionDouble& aOrientation)
+    : mParent(aParent),
+      mMatrixArray(nullptr),
+      mPosition(nullptr),
+      mOrientation(nullptr),
+      mInverse(nullptr),
+      mRawPosition(aPosition),
+      mRawOrientation(aOrientation),
+      mNeedsUpdate(true) {
+  mozilla::HoldJSObjects(this);
+  mRawTransformMatrix.SetRotationFromQuaternion(mRawOrientation);
+  mRawTransformMatrix.PostTranslate(mRawPosition);
+}
+
+XRRigidTransform::XRRigidTransform(nsISupports* aParent,
+                                   const gfx::Matrix4x4Double& aTransform)
+    : mParent(aParent),
+      mMatrixArray(nullptr),
+      mPosition(nullptr),
+      mOrientation(nullptr),
+      mInverse(nullptr),
+      mNeedsUpdate(true) {
+  mozilla::HoldJSObjects(this);
+  gfx::PointDouble3D scale;
+  mRawTransformMatrix = aTransform;
+  mRawTransformMatrix.Decompose(mRawPosition, mRawOrientation, scale);
+}
+
+XRRigidTransform::~XRRigidTransform() { mozilla::DropJSObjects(this); }
+
+/* static */ already_AddRefed<XRRigidTransform> XRRigidTransform::Constructor(
+    const GlobalObject& aGlobal, const DOMPointInit& aOrigin,
+    const DOMPointInit& aDirection, ErrorResult& aRv) {
+  gfx::PointDouble3D position(aOrigin.mX, aOrigin.mY, aOrigin.mZ);
+  gfx::QuaternionDouble orientation(aDirection.mX, aDirection.mY, aDirection.mZ,
+                                    aDirection.mW);
+  orientation.Normalize();
+  RefPtr<XRRigidTransform> obj =
+      new XRRigidTransform(aGlobal.GetAsSupports(), position, orientation);
+  return obj.forget();
+}
+
+JSObject* XRRigidTransform::WrapObject(JSContext* aCx,
+                                       JS::Handle<JSObject*> aGivenProto) {
+  return XRRigidTransform_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+DOMPoint* XRRigidTransform::Position() {
+  if (!mPosition) {
+    mPosition = new DOMPoint(mParent, mRawPosition.x, mRawPosition.y,
+                             mRawPosition.z, 1.0f);
+  }
+  return mPosition;
+}
+
+DOMPoint* XRRigidTransform::Orientation() {
+  if (!mOrientation) {
+    mOrientation = new DOMPoint(mParent, mRawOrientation.x, mRawOrientation.y,
+                                mRawOrientation.z, mRawOrientation.w);
+  }
+  return mOrientation;
+}
+
+XRRigidTransform& XRRigidTransform::operator=(const XRRigidTransform& aOther) {
+  Update(aOther.mRawPosition, aOther.mRawOrientation);
+  return *this;
+}
+
+gfx::QuaternionDouble XRRigidTransform::RawOrientation() const {
+  return mRawOrientation;
+}
+gfx::PointDouble3D XRRigidTransform::RawPosition() const {
+  return mRawPosition;
+}
+
+void XRRigidTransform::Update(const gfx::PointDouble3D& aPosition,
+                              const gfx::QuaternionDouble& aOrientation) {
+  mNeedsUpdate = true;
+  mRawPosition = aPosition;
+  mRawOrientation = aOrientation;
+  mRawTransformMatrix.SetRotationFromQuaternion(mRawOrientation);
+  mRawTransformMatrix.PostTranslate(mRawPosition);
+  UpdateInternal();
+}
+
+void XRRigidTransform::Update(const gfx::Matrix4x4Double& aTransform) {
+  mNeedsUpdate = true;
+  mRawTransformMatrix = aTransform;
+  gfx::PointDouble3D scale;
+  mRawTransformMatrix.Decompose(mRawPosition, mRawOrientation, scale);
+  UpdateInternal();
+}
+
+void XRRigidTransform::UpdateInternal() {
+  if (mPosition) {
+    mPosition->SetX(mRawPosition.x);
+    mPosition->SetY(mRawPosition.y);
+    mPosition->SetZ(mRawPosition.z);
+  }
+  if (mOrientation) {
+    mOrientation->SetX(mRawOrientation.x);
+    mOrientation->SetY(mRawOrientation.y);
+    mOrientation->SetZ(mRawOrientation.z);
+    mOrientation->SetW(mRawOrientation.w);
+  }
+  if (mInverse) {
+    gfx::Matrix4x4Double inverseMatrix = mRawTransformMatrix;
+    Unused << inverseMatrix.Invert();
+    mInverse->Update(inverseMatrix);
+  }
+}
+
+void XRRigidTransform::GetMatrix(JSContext* aCx,
+                                 JS::MutableHandle<JSObject*> aRetval,
+                                 ErrorResult& aRv) {
+  if (!mMatrixArray || mNeedsUpdate) {
+    mNeedsUpdate = false;
+
+    const uint32_t size = 16;
+    float components[size] = {};
+    // In order to avoid some platforms which only copy
+    // the first or last two bytes of a Float64 to a Float32.
+    for (uint32_t i = 0; i < size; ++i) {
+      components[i] = mRawTransformMatrix.components[i];
+    }
+    Pose::SetFloat32Array(aCx, this, aRetval, mMatrixArray, components, 16,
+                          aRv);
+    if (!mMatrixArray) {
+      return;
+    }
+  }
+  if (mMatrixArray) {
+    JS::ExposeObjectToActiveJS(mMatrixArray);
+  }
+  aRetval.set(mMatrixArray);
+}
+
+already_AddRefed<XRRigidTransform> XRRigidTransform::Inverse() {
+  if (!mInverse) {
+    gfx::Matrix4x4Double inverseMatrix = mRawTransformMatrix;
+    Unused << inverseMatrix.Invert();
+    mInverse = new XRRigidTransform(mParent, inverseMatrix);
+  }
+
+  RefPtr<XRRigidTransform> inverse = mInverse;
+  return inverse.forget();
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRRigidTransform.h b/dom/vr/XRRigidTransform.h
new file mode 100644
index 0000000000..ff6bf25b50
--- /dev/null
+++ b/dom/vr/XRRigidTransform.h
@@ -0,0 +1,69 @@
+/* -*- 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_XRRigidTransform_h_
+#define mozilla_dom_XRRigidTransform_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class VRFrameData;
+
+class XRRigidTransform final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(XRRigidTransform)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(XRRigidTransform)
+
+  explicit XRRigidTransform(nsISupports* aParent,
+                            const gfx::PointDouble3D& aPosition,
+                            const gfx::QuaternionDouble& aOrientation);
+  explicit XRRigidTransform(nsISupports* aParent,
+                            const gfx::Matrix4x4Double& aTransform);
+  static already_AddRefed<XRRigidTransform> Constructor(
+      const GlobalObject& aGlobal, const DOMPointInit& aOrigin,
+      const DOMPointInit& aDirection, ErrorResult& aRv);
+  XRRigidTransform& operator=(const XRRigidTransform& aOther);
+  gfx::QuaternionDouble RawOrientation() const;
+  gfx::PointDouble3D RawPosition() const;
+  void Update(const gfx::PointDouble3D& aPosition,
+              const gfx::QuaternionDouble& aOrientation);
+  void Update(const gfx::Matrix4x4Double& aTransform);
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  DOMPoint* Position();
+  DOMPoint* Orientation();
+  void GetMatrix(JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                 ErrorResult& aRv);
+  already_AddRefed<XRRigidTransform> Inverse();
+
+ protected:
+  void UpdateInternal();
+  virtual ~XRRigidTransform();
+
+  nsCOMPtr<nsISupports> mParent;
+  JS::Heap<JSObject*> mMatrixArray;
+  RefPtr<DOMPoint> mPosition;
+  RefPtr<DOMPoint> mOrientation;
+  RefPtr<XRRigidTransform> mInverse;
+  gfx::Matrix4x4Double mRawTransformMatrix;
+  gfx::PointDouble3D mRawPosition;
+  gfx::QuaternionDouble mRawOrientation;
+  bool mNeedsUpdate;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRRigidTransform_h_
diff --git a/dom/vr/XRSession.cpp b/dom/vr/XRSession.cpp
new file mode 100644
index 0000000000..016e7a0bc5
--- /dev/null
+++ b/dom/vr/XRSession.cpp
@@ -0,0 +1,523 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRSession.h"
+
+#include "mozilla/dom/XRSessionEvent.h"
+#include "mozilla/dom/XRInputSourceEvent.h"
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/dom/DocumentInlines.h"
+#include "mozilla/dom/Promise.h"
+#include "XRSystem.h"
+#include "XRRenderState.h"
+#include "XRBoundedReferenceSpace.h"
+#include "XRFrame.h"
+#include "XRNativeOrigin.h"
+#include "XRNativeOriginFixed.h"
+#include "XRNativeOriginViewer.h"
+#include "XRNativeOriginLocal.h"
+#include "XRNativeOriginLocalFloor.h"
+#include "XRView.h"
+#include "XRViewerPose.h"
+#include "VRLayerChild.h"
+#include "XRInputSourceArray.h"
+#include "nsGlobalWindow.h"
+#include "nsIObserverService.h"
+#include "nsISupportsPrimitives.h"
+#include "nsRefreshDriver.h"
+#include "VRDisplayClient.h"
+#include "VRDisplayPresentation.h"
+
+/**
+ * Maximum instances of XRFrame and XRViewerPose objects
+ * created in the pool.
+ */
+const uint32_t kMaxPoolSize = 16;
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRSession)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(XRSession,
+                                                  DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mXRSystem)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mActiveRenderState)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingRenderState)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInputSources)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mViewerPosePool)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFramePool)
+
+  for (uint32_t i = 0; i < tmp->mFrameRequestCallbacks.Length(); ++i) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mFrameRequestCallbacks[i]");
+    cb.NoteXPCOMChild(tmp->mFrameRequestCallbacks[i].mCallback);
+  }
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(XRSession, DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mXRSystem)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mActiveRenderState)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mPendingRenderState)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mInputSources)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mViewerPosePool)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mFramePool)
+
+  tmp->mFrameRequestCallbacks.Clear();
+
+  // Don't need NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER because
+  // DOMEventTargetHelper does it for us.
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(XRSession, DOMEventTargetHelper)
+
+already_AddRefed<XRSession> XRSession::CreateInlineSession(
+    nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+    const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes) {
+  nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(aWindow);
+  if (!win) {
+    return nullptr;
+  }
+  Document* doc = aWindow->GetExtantDoc();
+  if (!doc) {
+    return nullptr;
+  }
+  nsPresContext* context = doc->GetPresContext();
+  if (!context) {
+    return nullptr;
+  }
+  nsRefreshDriver* driver = context->RefreshDriver();
+  if (!driver) {
+    return nullptr;
+  }
+
+  RefPtr<XRSession> session =
+      new XRSession(aWindow, aXRSystem, driver, nullptr, gfx::kVRGroupContent,
+                    aEnabledReferenceSpaceTypes);
+  driver->AddRefreshObserver(session, FlushType::Display, "XR Session");
+  return session.forget();
+}
+
+already_AddRefed<XRSession> XRSession::CreateImmersiveSession(
+    nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+    gfx::VRDisplayClient* aClient, uint32_t aPresentationGroup,
+    const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes) {
+  RefPtr<XRSession> session =
+      new XRSession(aWindow, aXRSystem, nullptr, aClient, aPresentationGroup,
+                    aEnabledReferenceSpaceTypes);
+  return session.forget();
+}
+
+XRSession::XRSession(
+    nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+    nsRefreshDriver* aRefreshDriver, gfx::VRDisplayClient* aClient,
+    uint32_t aPresentationGroup,
+    const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes)
+    : DOMEventTargetHelper(aWindow),
+      mXRSystem(aXRSystem),
+      mShutdown(false),
+      mEnded(false),
+      mRefreshDriver(aRefreshDriver),
+      mDisplayClient(aClient),
+      mFrameRequestCallbackCounter(0),
+      mEnabledReferenceSpaceTypes(aEnabledReferenceSpaceTypes.Clone()),
+      mViewerPosePoolIndex(0),
+      mFramePoolIndex(0) {
+  if (aClient) {
+    aClient->SessionStarted(this);
+  }
+  mActiveRenderState = new XRRenderState(aWindow, this);
+  mStartTimeStamp = TimeStamp::Now();
+  if (IsImmersive()) {
+    mDisplayPresentation =
+        mDisplayClient->BeginPresentation({}, aPresentationGroup);
+  }
+  if (mDisplayClient) {
+    mDisplayClient->SetXRAPIMode(gfx::VRAPIMode::WebXR);
+  }
+  // TODO: Handle XR input sources are no longer available cases.
+  // https://immersive-web.github.io/webxr/#dom-xrsession-inputsources
+  mInputSources = new XRInputSourceArray(aWindow);
+}
+
+XRSession::~XRSession() { MOZ_ASSERT(mShutdown); }
+
+gfx::VRDisplayClient* XRSession::GetDisplayClient() const {
+  return mDisplayClient;
+}
+
+JSObject* XRSession::WrapObject(JSContext* aCx,
+                                JS::Handle<JSObject*> aGivenProto) {
+  return XRSession_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+bool XRSession::IsEnded() const { return mEnded; }
+
+already_AddRefed<Promise> XRSession::End(ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  NS_ENSURE_TRUE(global, nullptr);
+
+  ExitPresentInternal();
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  promise->MaybeResolve(JS::UndefinedHandleValue);
+
+  return promise.forget();
+}
+
+bool XRSession::IsImmersive() const {
+  // Only immersive sessions have a VRDisplayClient
+  return mDisplayClient != nullptr;
+}
+
+XRVisibilityState XRSession::VisibilityState() {
+  return XRVisibilityState::Visible;
+  // TODO (Bug 1609771): Implement changing visibility state
+}
+
+// https://immersive-web.github.io/webxr/#dom-xrsession-updaterenderstate
+void XRSession::UpdateRenderState(const XRRenderStateInit& aNewState,
+                                  ErrorResult& aRv) {
+  if (mEnded) {
+    aRv.ThrowInvalidStateError(
+        "UpdateRenderState can not be called on an XRSession that has ended.");
+    return;
+  }
+  if (aNewState.mBaseLayer.WasPassed() &&
+      aNewState.mBaseLayer.Value()->mSession != this) {
+    aRv.ThrowInvalidStateError(
+        "The baseLayer passed in to UpdateRenderState must "
+        "belong to the XRSession that UpdateRenderState is "
+        "being called on.");
+    return;
+  }
+  if (aNewState.mInlineVerticalFieldOfView.WasPassed() && IsImmersive()) {
+    aRv.ThrowInvalidStateError(
+        "The inlineVerticalFieldOfView can not be set on an "
+        "XRRenderState for an immersive XRSession.");
+    return;
+  }
+  if (mPendingRenderState == nullptr) {
+    mPendingRenderState = new XRRenderState(*mActiveRenderState);
+  }
+  if (aNewState.mDepthNear.WasPassed()) {
+    mPendingRenderState->SetDepthNear(aNewState.mDepthNear.Value());
+  }
+  if (aNewState.mDepthFar.WasPassed()) {
+    mPendingRenderState->SetDepthFar(aNewState.mDepthFar.Value());
+  }
+  if (aNewState.mInlineVerticalFieldOfView.WasPassed()) {
+    mPendingRenderState->SetInlineVerticalFieldOfView(
+        aNewState.mInlineVerticalFieldOfView.Value());
+  }
+  if (aNewState.mBaseLayer.WasPassed()) {
+    mPendingRenderState->SetBaseLayer(aNewState.mBaseLayer.Value());
+  }
+}
+
+XRRenderState* XRSession::RenderState() { return mActiveRenderState; }
+
+XRInputSourceArray* XRSession::InputSources() { return mInputSources; }
+
+// https://immersive-web.github.io/webxr/#apply-the-pending-render-state
+void XRSession::ApplyPendingRenderState() {
+  if (mPendingRenderState == nullptr) {
+    return;
+  }
+  mActiveRenderState = mPendingRenderState;
+  mPendingRenderState = nullptr;
+
+  // https://immersive-web.github.io/webxr/#minimum-inline-field-of-view
+  const double kMinimumInlineVerticalFieldOfView = 0.0f;
+
+  // https://immersive-web.github.io/webxr/#maximum-inline-field-of-view
+  const double kMaximumInlineVerticalFieldOfView = M_PI;
+
+  if (!mActiveRenderState->GetInlineVerticalFieldOfView().IsNull()) {
+    double verticalFOV =
+        mActiveRenderState->GetInlineVerticalFieldOfView().Value();
+    if (verticalFOV < kMinimumInlineVerticalFieldOfView) {
+      verticalFOV = kMinimumInlineVerticalFieldOfView;
+    }
+    if (verticalFOV > kMaximumInlineVerticalFieldOfView) {
+      verticalFOV = kMaximumInlineVerticalFieldOfView;
+    }
+    mActiveRenderState->SetInlineVerticalFieldOfView(verticalFOV);
+  }
+
+  // Our minimum near plane value is set to a small value close but not equal to
+  // zero (kEpsilon) The maximum far plane is infinite.
+  const float kEpsilon = 0.00001f;
+  double depthNear = mActiveRenderState->DepthNear();
+  double depthFar = mActiveRenderState->DepthFar();
+  if (depthNear < 0.0f) {
+    depthNear = 0.0f;
+  }
+  if (depthFar < 0.0f) {
+    depthFar = 0.0f;
+  }
+  // Ensure at least a small distance between the near and far planes
+  if (fabs(depthFar - depthNear) < kEpsilon) {
+    depthFar = depthNear + kEpsilon;
+  }
+  mActiveRenderState->SetDepthNear(depthNear);
+  mActiveRenderState->SetDepthFar(depthFar);
+
+  XRWebGLLayer* baseLayer = mActiveRenderState->GetBaseLayer();
+  if (baseLayer) {
+    if (!IsImmersive() && baseLayer->mCompositionDisabled) {
+      mActiveRenderState->SetCompositionDisabled(true);
+      mActiveRenderState->SetOutputCanvas(baseLayer->GetCanvas());
+    } else {
+      mActiveRenderState->SetCompositionDisabled(false);
+      mActiveRenderState->SetOutputCanvas(nullptr);
+      mDisplayPresentation->UpdateXRWebGLLayer(baseLayer);
+    }
+  }  // if (baseLayer)
+}
+
+void XRSession::WillRefresh(mozilla::TimeStamp aTime) {
+  // Inline sessions are driven by nsRefreshDriver directly,
+  // unlike immersive sessions, which are driven VRDisplayClient.
+  if (!IsImmersive() && !mXRSystem->HasActiveImmersiveSession()) {
+    nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(GetOwner());
+    if (win) {
+      if (JSObject* obj = win->AsGlobal()->GetGlobalJSObject()) {
+        js::NotifyAnimationActivity(obj);
+      }
+    }
+    StartFrame();
+  }
+}
+
+void XRSession::StartFrame() {
+  if (mShutdown || mEnded) {
+    return;
+  }
+  ApplyPendingRenderState();
+
+  XRWebGLLayer* baseLayer = mActiveRenderState->GetBaseLayer();
+  if (!baseLayer) {
+    return;
+  }
+
+  if (!IsImmersive() && mActiveRenderState->GetOutputCanvas() == nullptr) {
+    return;
+  }
+
+  // Determine timestamp for the callbacks
+  TimeStamp nowTime = TimeStamp::Now();
+  mozilla::TimeDuration duration = nowTime - mStartTimeStamp;
+  DOMHighResTimeStamp timeStamp = duration.ToMilliseconds();
+
+  // Create an XRFrame for the callbacks
+  RefPtr<XRFrame> frame = PooledFrame();
+  frame->StartAnimationFrame();
+
+  baseLayer->StartAnimationFrame();
+  nsTArray<XRFrameRequest> callbacks;
+  callbacks.AppendElements(mFrameRequestCallbacks);
+  mFrameRequestCallbacks.Clear();
+  for (auto& callback : callbacks) {
+    callback.Call(timeStamp, *frame);
+  }
+
+  baseLayer->EndAnimationFrame();
+  frame->EndAnimationFrame();
+  if (mDisplayPresentation) {
+    mDisplayPresentation->SubmitFrame();
+  }
+}
+
+void XRSession::ExitPresent() { ExitPresentInternal(); }
+
+already_AddRefed<Promise> XRSession::RequestReferenceSpace(
+    const XRReferenceSpaceType& aReferenceSpaceType, ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  NS_ENSURE_TRUE(global, nullptr);
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  if (!mEnabledReferenceSpaceTypes.Contains(aReferenceSpaceType)) {
+    promise->MaybeRejectWithNotSupportedError(nsLiteralCString(
+        "Requested XRReferenceSpaceType not available for the XRSession."));
+    return promise.forget();
+  }
+  RefPtr<XRReferenceSpace> space;
+  RefPtr<XRNativeOrigin> nativeOrigin;
+  if (mDisplayClient) {
+    switch (aReferenceSpaceType) {
+      case XRReferenceSpaceType::Viewer:
+        nativeOrigin = new XRNativeOriginViewer(mDisplayClient);
+        break;
+      case XRReferenceSpaceType::Local:
+        nativeOrigin = new XRNativeOriginLocal(mDisplayClient);
+        break;
+      case XRReferenceSpaceType::Local_floor:
+      case XRReferenceSpaceType::Bounded_floor:
+        nativeOrigin = new XRNativeOriginLocalFloor(mDisplayClient);
+        break;
+      default:
+        nativeOrigin = new XRNativeOriginFixed(gfx::PointDouble3D());
+        break;
+    }
+  } else {
+    // We currently only support XRReferenceSpaceType::Viewer when
+    // there is no XR hardware.  In this case, the native origin
+    // will always be at {0, 0, 0} which will always be the same
+    // as the 'tracked' position of the non-existant pose.
+    MOZ_ASSERT(aReferenceSpaceType == XRReferenceSpaceType::Viewer);
+    nativeOrigin = new XRNativeOriginFixed(gfx::PointDouble3D());
+  }
+  if (aReferenceSpaceType == XRReferenceSpaceType::Bounded_floor) {
+    space = new XRBoundedReferenceSpace(GetParentObject(), this, nativeOrigin);
+  } else {
+    space = new XRReferenceSpace(GetParentObject(), this, nativeOrigin,
+                                 aReferenceSpaceType);
+  }
+
+  promise->MaybeResolve(space);
+  return promise.forget();
+}
+
+XRRenderState* XRSession::GetActiveRenderState() const {
+  return mActiveRenderState;
+}
+
+void XRSession::XRFrameRequest::Call(const DOMHighResTimeStamp& aTimeStamp,
+                                     XRFrame& aFrame) {
+  RefPtr<mozilla::dom::XRFrameRequestCallback> callback = mCallback;
+  callback->Call(aTimeStamp, aFrame);
+}
+
+int32_t XRSession::RequestAnimationFrame(XRFrameRequestCallback& aCallback,
+                                         ErrorResult& aError) {
+  if (mShutdown) {
+    return 0;
+  }
+
+  int32_t handle = ++mFrameRequestCallbackCounter;
+
+  mFrameRequestCallbacks.AppendElement(XRFrameRequest(aCallback, handle));
+
+  return handle;
+}
+
+void XRSession::CancelAnimationFrame(int32_t aHandle, ErrorResult& aError) {
+  mFrameRequestCallbacks.RemoveElementSorted(aHandle);
+}
+
+void XRSession::Shutdown() {
+  mShutdown = true;
+  ExitPresentInternal();
+  mViewerPosePool.Clear();
+  mViewerPosePoolIndex = 0;
+  mFramePool.Clear();
+  mFramePoolIndex = 0;
+  mActiveRenderState = nullptr;
+  mPendingRenderState = nullptr;
+  mFrameRequestCallbacks.Clear();
+
+  // Unregister from nsRefreshObserver
+  if (mRefreshDriver) {
+    mRefreshDriver->RemoveRefreshObserver(this, FlushType::Display);
+    mRefreshDriver = nullptr;
+  }
+}
+
+void XRSession::ExitPresentInternal() {
+  if (mInputSources) {
+    mInputSources->Clear(this);
+  }
+  if (mDisplayClient) {
+    mDisplayClient->SessionEnded(this);
+  }
+
+  if (mXRSystem) {
+    mXRSystem->SessionEnded(this);
+  }
+
+  if (mActiveRenderState) {
+    mActiveRenderState->SessionEnded();
+  }
+
+  if (mPendingRenderState) {
+    mPendingRenderState->SessionEnded();
+  }
+
+  mDisplayPresentation = nullptr;
+  if (!mEnded) {
+    mEnded = true;
+
+    XRSessionEventInit init;
+    init.mBubbles = false;
+    init.mCancelable = false;
+    init.mSession = this;
+    RefPtr<XRSessionEvent> event =
+        XRSessionEvent::Constructor(this, u"end"_ns, init);
+
+    event->SetTrusted(true);
+    this->DispatchEvent(*event);
+  }
+}
+
+void XRSession::DisconnectFromOwner() {
+  MOZ_ASSERT(NS_IsMainThread());
+  Shutdown();
+  DOMEventTargetHelper::DisconnectFromOwner();
+}
+
+void XRSession::LastRelease() {
+  // We don't want to wait for the GC to free up the presentation
+  // for use in other documents, so we do this in LastRelease().
+  Shutdown();
+}
+
+RefPtr<XRViewerPose> XRSession::PooledViewerPose(
+    const gfx::Matrix4x4Double& aTransform, bool aEmulatedPosition) {
+  RefPtr<XRViewerPose> pose;
+  if (mViewerPosePool.Length() > mViewerPosePoolIndex) {
+    pose = mViewerPosePool.ElementAt(mViewerPosePoolIndex);
+    pose->Transform()->Update(aTransform);
+    pose->SetEmulatedPosition(aEmulatedPosition);
+  } else {
+    RefPtr<XRRigidTransform> transform = new XRRigidTransform(this, aTransform);
+    nsTArray<RefPtr<XRView>> views;
+    if (IsImmersive()) {
+      views.AppendElement(new XRView(GetParentObject(), XREye::Left));
+      views.AppendElement(new XRView(GetParentObject(), XREye::Right));
+    } else {
+      views.AppendElement(new XRView(GetParentObject(), XREye::None));
+    }
+    pose = new XRViewerPose(this, transform, aEmulatedPosition, views);
+    mViewerPosePool.AppendElement(pose);
+  }
+
+  mViewerPosePoolIndex++;
+  if (mViewerPosePoolIndex >= kMaxPoolSize) {
+    mViewerPosePoolIndex = 0;
+  }
+
+  return pose;
+}
+
+RefPtr<XRFrame> XRSession::PooledFrame() {
+  RefPtr<XRFrame> frame;
+  if (mFramePool.Length() > mFramePoolIndex) {
+    frame = mFramePool.ElementAt(mFramePoolIndex);
+  } else {
+    frame = new XRFrame(GetParentObject(), this);
+    mFramePool.AppendElement(frame);
+  }
+
+  return frame;
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRSession.h b/dom/vr/XRSession.h
new file mode 100644
index 0000000000..322a71dae4
--- /dev/null
+++ b/dom/vr/XRSession.h
@@ -0,0 +1,153 @@
+/* -*- 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_XRSession_h_
+#define mozilla_dom_XRSession_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "nsRefreshObservers.h"
+
+#include "gfxVR.h"
+
+class nsRefreshDriver;
+
+namespace mozilla {
+namespace gfx {
+class VRDisplayClient;
+class VRDisplayPresentation;
+}  // namespace gfx
+namespace dom {
+
+class XRSystem;
+enum class XREye : uint8_t;
+enum class XRReferenceSpaceType : uint8_t;
+enum class XRSessionMode : uint8_t;
+enum class XRVisibilityState : uint8_t;
+class XRFrame;
+class XRFrameRequestCallback;
+class XRInputSource;
+class XRInputSourceArray;
+class XRLayer;
+struct XRReferenceSpaceOptions;
+class XRRenderState;
+struct XRRenderStateInit;
+class XRSpace;
+class XRViewerPose;
+
+class XRSession final : public DOMEventTargetHelper, public nsARefreshObserver {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XRSession, DOMEventTargetHelper)
+
+ private:
+  explicit XRSession(
+      nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+      nsRefreshDriver* aRefreshDriver, gfx::VRDisplayClient* aClient,
+      uint32_t aPresentationGroup,
+      const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes);
+
+ public:
+  static already_AddRefed<XRSession> CreateInlineSession(
+      nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+      const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes);
+  static already_AddRefed<XRSession> CreateImmersiveSession(
+      nsPIDOMWindowInner* aWindow, XRSystem* aXRSystem,
+      gfx::VRDisplayClient* aClient, uint32_t aPresentationGroup,
+      const nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes);
+
+  // WebIDL Boilerplate
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Attributes
+  XRVisibilityState VisibilityState();
+  XRRenderState* RenderState();
+  XRInputSourceArray* InputSources();
+
+  // WebIDL Methods
+  void UpdateRenderState(const XRRenderStateInit& aNewState, ErrorResult& aRv);
+  already_AddRefed<Promise> RequestReferenceSpace(
+      const XRReferenceSpaceType& aReferenceSpaceType, ErrorResult& aRv);
+  int32_t RequestAnimationFrame(XRFrameRequestCallback& aCallback,
+                                mozilla::ErrorResult& aError);
+  void CancelAnimationFrame(int32_t aHandle, mozilla::ErrorResult& aError);
+  already_AddRefed<Promise> End(ErrorResult& aRv);
+
+  // WebIDL Events
+  IMPL_EVENT_HANDLER(end);
+  IMPL_EVENT_HANDLER(inputsourceschange);
+  IMPL_EVENT_HANDLER(select);
+  IMPL_EVENT_HANDLER(selectstart);
+  IMPL_EVENT_HANDLER(selectend);
+  IMPL_EVENT_HANDLER(squeeze);
+  IMPL_EVENT_HANDLER(squeezestart);
+  IMPL_EVENT_HANDLER(squeezeend);
+  IMPL_EVENT_HANDLER(visibilitychange);
+
+  // Non WebIDL Members
+  gfx::VRDisplayClient* GetDisplayClient() const;
+  XRRenderState* GetActiveRenderState() const;
+  bool IsEnded() const;
+  bool IsImmersive() const;
+  MOZ_CAN_RUN_SCRIPT
+  void StartFrame();
+  void ExitPresent();
+  RefPtr<XRViewerPose> PooledViewerPose(const gfx::Matrix4x4Double& aTransform,
+                                        bool aEmulatedPosition);
+
+  // nsARefreshObserver
+  MOZ_CAN_RUN_SCRIPT
+  void WillRefresh(mozilla::TimeStamp aTime) override;
+
+ protected:
+  virtual ~XRSession();
+  void LastRelease() override;
+  void DisconnectFromOwner() override;
+  void Shutdown();
+  void ExitPresentInternal();
+  void ApplyPendingRenderState();
+  RefPtr<XRFrame> PooledFrame();
+  RefPtr<XRSystem> mXRSystem;
+  bool mShutdown;
+  bool mEnded;
+  RefPtr<nsRefreshDriver> mRefreshDriver;
+  RefPtr<gfx::VRDisplayClient> mDisplayClient;
+  RefPtr<gfx::VRDisplayPresentation> mDisplayPresentation;
+  RefPtr<XRRenderState> mActiveRenderState;
+  RefPtr<XRRenderState> mPendingRenderState;
+  RefPtr<XRInputSourceArray> mInputSources;
+
+  struct XRFrameRequest {
+    XRFrameRequest(mozilla::dom::XRFrameRequestCallback& aCallback,
+                   int32_t aHandle)
+        : mCallback(&aCallback), mHandle(aHandle) {}
+    MOZ_CAN_RUN_SCRIPT
+    void Call(const DOMHighResTimeStamp& aTimeStamp, XRFrame& aFrame);
+
+    // Comparator operators to allow RemoveElementSorted with an
+    // integer argument on arrays of XRFrameRequest
+    bool operator==(int32_t aHandle) const { return mHandle == aHandle; }
+    bool operator<(int32_t aHandle) const { return mHandle < aHandle; }
+
+    RefPtr<mozilla::dom::XRFrameRequestCallback> mCallback;
+    int32_t mHandle;
+  };
+
+  int32_t mFrameRequestCallbackCounter;
+  nsTArray<XRFrameRequest> mFrameRequestCallbacks;
+  mozilla::TimeStamp mStartTimeStamp;
+  nsTArray<XRReferenceSpaceType> mEnabledReferenceSpaceTypes;
+  nsTArray<RefPtr<XRViewerPose>> mViewerPosePool;
+  uint32_t mViewerPosePoolIndex;
+  nsTArray<RefPtr<XRFrame>> mFramePool;
+  uint32_t mFramePoolIndex;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRSession_h_
diff --git a/dom/vr/XRSpace.cpp b/dom/vr/XRSpace.cpp
new file mode 100644
index 0000000000..172111c809
--- /dev/null
+++ b/dom/vr/XRSpace.cpp
@@ -0,0 +1,83 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRSpace.h"
+#include "mozilla/dom/XRRigidTransform.h"
+#include "VRDisplayClient.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRSpace)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(XRSpace, DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSession)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(XRSpace, DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mSession)
+  // Don't need NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER because
+  // DOMEventTargetHelper does it for us.
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(XRSpace, DOMEventTargetHelper)
+
+XRSpace::XRSpace(nsIGlobalObject* aParent, XRSession* aSession,
+                 XRNativeOrigin* aNativeOrigin)
+    : DOMEventTargetHelper(aParent),
+      mSession(aSession),
+      mNativeOrigin(aNativeOrigin),
+      mOriginOffsetPosition(0.0f, 0.0f, 0.0f),
+      mOriginOffsetOrientation(0.0f, 0.0f, 0.0f, 1.0f) {}
+
+JSObject* XRSpace::WrapObject(JSContext* aCx,
+                              JS::Handle<JSObject*> aGivenProto) {
+  return XRSpace_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+XRSession* XRSpace::GetSession() const { return mSession; }
+
+gfx::QuaternionDouble XRSpace::GetEffectiveOriginOrientation() const {
+  gfx::QuaternionDouble orientation =
+      mNativeOrigin->GetOrientation() * mOriginOffsetOrientation;
+  return orientation;
+}
+
+gfx::PointDouble3D XRSpace::GetEffectiveOriginPosition() const {
+  gfx::PointDouble3D position;
+  position = mNativeOrigin->GetPosition();
+  position = mOriginOffsetOrientation.RotatePoint(position);
+  position += mOriginOffsetPosition;
+  return position;
+}
+
+gfx::Matrix4x4Double XRSpace::GetEffectiveOriginTransform() const {
+  gfx::Matrix4x4Double transform;
+  transform.SetRotationFromQuaternion(GetEffectiveOriginOrientation());
+  transform.PostTranslate(GetEffectiveOriginPosition());
+  return transform;
+}
+
+bool XRSpace::IsPositionEmulated() const {
+  gfx::VRDisplayClient* display = mSession->GetDisplayClient();
+  if (!display) {
+    // When there are no sensors, the position is considered emulated.
+    return true;
+  }
+  const gfx::VRDisplayInfo& displayInfo = display->GetDisplayInfo();
+  if (displayInfo.GetCapabilities() &
+      gfx::VRDisplayCapabilityFlags::Cap_PositionEmulated) {
+    // Cap_PositionEmulated indicates that the position is always emulated.
+    return true;
+  }
+  const gfx::VRHMDSensorState& sensorState = display->GetSensorState();
+  // When positional tracking is lost, the position is considered emulated.
+  return ((sensorState.flags & gfx::VRDisplayCapabilityFlags::Cap_Position) ==
+          gfx::VRDisplayCapabilityFlags::Cap_None);
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRSpace.h b/dom/vr/XRSpace.h
new file mode 100644
index 0000000000..c1ba6459d9
--- /dev/null
+++ b/dom/vr/XRSpace.h
@@ -0,0 +1,58 @@
+/* -*- 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_XRSpace_h_
+#define mozilla_dom_XRSpace_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "XRNativeOrigin.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRRigidTransform;
+class XRSession;
+
+class XRSpace : public DOMEventTargetHelper {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XRSpace, DOMEventTargetHelper)
+
+  explicit XRSpace(nsIGlobalObject* aParent, XRSession* aSession,
+                   XRNativeOrigin* aNativeOrigin);
+
+  // WebIDL Boilerplate
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  XRSession* GetSession() const;
+  XRNativeOrigin* GetNativeOrigin() const;
+
+  // Non webIDL Members
+  gfx::QuaternionDouble GetEffectiveOriginOrientation() const;
+  gfx::PointDouble3D GetEffectiveOriginPosition() const;
+  gfx::Matrix4x4Double GetEffectiveOriginTransform() const;
+  virtual bool IsPositionEmulated() const;
+
+ protected:
+  virtual ~XRSpace() = default;
+
+  RefPtr<XRSession> mSession;
+  RefPtr<XRNativeOrigin> mNativeOrigin;
+
+  // https://immersive-web.github.io/webxr/#xrspace-origin-offset
+  // Origin Offset, represented as a rigid transform
+  gfx::PointDouble3D mOriginOffsetPosition;
+  gfx::QuaternionDouble mOriginOffsetOrientation;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRSpace_h_
diff --git a/dom/vr/XRSystem.cpp b/dom/vr/XRSystem.cpp
new file mode 100644
index 0000000000..a8765ea8ba
--- /dev/null
+++ b/dom/vr/XRSystem.cpp
@@ -0,0 +1,711 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRSystem.h"
+
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/dom/XRPermissionRequest.h"
+#include "mozilla/dom/XRSession.h"
+#include "mozilla/dom/BindingCallContext.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/FeaturePolicyUtils.h"
+#include "mozilla/dom/PermissionMessageUtils.h"
+#include "nsGlobalWindow.h"
+#include "nsThreadUtils.h"
+#include "gfxVR.h"
+#include "VRDisplayClient.h"
+#include "VRManagerChild.h"
+
+namespace mozilla {
+namespace dom {
+
+using namespace gfx;
+
+////////////////////////////////////////////////////////////////////////////////
+// XRSystem cycle collection
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRSystem)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(XRSystem,
+                                                  DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mActiveImmersiveSession)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInlineSessions)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mIsSessionSupportedRequests)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(
+      mRequestSessionRequestsWaitingForRuntimeDetection)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRequestSessionRequestsWithoutHardware)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(
+      mRequestSessionRequestsWaitingForEnumeration)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(XRSystem, DOMEventTargetHelper)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mActiveImmersiveSession)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mInlineSessions)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mIsSessionSupportedRequests)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(
+      mRequestSessionRequestsWaitingForRuntimeDetection)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mRequestSessionRequestsWithoutHardware)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mRequestSessionRequestsWaitingForEnumeration)
+  // Don't need NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER because
+  // DOMEventTargetHelper does it for us.
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(XRSystem, DOMEventTargetHelper)
+
+JSObject* XRSystem::WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) {
+  return XRSystem_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+// static
+already_AddRefed<XRSystem> XRSystem::Create(nsPIDOMWindowInner* aWindow) {
+  MOZ_ASSERT(aWindow);
+
+  RefPtr<XRSystem> service = new XRSystem(aWindow);
+  return service.forget();
+}
+
+XRSystem::XRSystem(nsPIDOMWindowInner* aWindow)
+    : DOMEventTargetHelper(aWindow),
+      mShuttingDown(false),
+      mPendingImmersiveSession(false),
+      mEnumerationInFlight(false) {
+  // Unregister with VRManagerChild
+  VRManagerChild* vmc = VRManagerChild::Get();
+  if (vmc) {
+    vmc->AddListener(this);
+  }
+}
+
+void XRSystem::Shutdown() {
+  MOZ_ASSERT(!mShuttingDown);
+  mShuttingDown = true;
+
+  // Unregister from VRManagerChild
+  if (VRManagerChild::IsCreated()) {
+    VRManagerChild* vmc = VRManagerChild::Get();
+    vmc->RemoveListener(this);
+  }
+}
+
+void XRSystem::SessionEnded(XRSession* aSession) {
+  if (mActiveImmersiveSession == aSession) {
+    mActiveImmersiveSession = nullptr;
+  }
+  mInlineSessions.RemoveElement(aSession);
+}
+
+already_AddRefed<Promise> XRSystem::IsSessionSupported(XRSessionMode aMode,
+                                                       ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  NS_ENSURE_TRUE(global, nullptr);
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  if (aMode == XRSessionMode::Inline) {
+    promise->MaybeResolve(true);
+    return promise.forget();
+  }
+
+  if (mIsSessionSupportedRequests.IsEmpty()) {
+    gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+    vm->DetectRuntimes();
+  }
+
+  RefPtr<IsSessionSupportedRequest> request =
+      new IsSessionSupportedRequest(aMode, promise);
+  mIsSessionSupportedRequests.AppendElement(request);
+  return promise.forget();
+}
+
+already_AddRefed<Promise> XRSystem::RequestSession(
+    JSContext* aCx, XRSessionMode aMode, const XRSessionInit& aOptions,
+    CallerType aCallerType, ErrorResult& aRv) {
+  nsCOMPtr<nsIGlobalObject> global = GetParentObject();
+  NS_ENSURE_TRUE(global, nullptr);
+
+  RefPtr<Promise> promise = Promise::Create(global, aRv);
+  NS_ENSURE_TRUE(!aRv.Failed(), nullptr);
+
+  bool immersive = (aMode == XRSessionMode::Immersive_vr ||
+                    aMode == XRSessionMode::Immersive_ar);
+
+  // The document must be a responsible document, active and focused.
+  nsCOMPtr<Document> responsibleDocument = GetDocumentIfCurrent();
+  if (!responsibleDocument) {
+    // The document is not trustworthy
+    promise->MaybeRejectWithSecurityError("This document is not responsible.");
+    return promise.forget();
+  }
+
+  if (immersive || aOptions.mRequiredFeatures.WasPassed() ||
+      aOptions.mOptionalFeatures.WasPassed()) {
+    if (!responsibleDocument->HasValidTransientUserGestureActivation() &&
+        aCallerType != CallerType::System &&
+        StaticPrefs::dom_vr_require_gesture()) {
+      // A user gesture is required.
+      promise->MaybeRejectWithSecurityError("A user gesture is required.");
+      return promise.forget();
+    }
+  }
+
+  nsTArray<XRReferenceSpaceType> requiredReferenceSpaceTypes;
+  nsTArray<XRReferenceSpaceType> optionalReferenceSpaceTypes;
+
+  /**
+   * By default, all sessions will require XRReferenceSpaceType::Viewer
+   * and immersive sessions will require XRReferenceSpaceType::Local.
+   *
+   * https://www.w3.org/TR/webxr/#default-features
+   */
+  requiredReferenceSpaceTypes.AppendElement(XRReferenceSpaceType::Viewer);
+  if (immersive) {
+    requiredReferenceSpaceTypes.AppendElement(XRReferenceSpaceType::Local);
+  }
+
+  BindingCallContext callCx(aCx, "XRSystem.requestSession");
+
+  if (aOptions.mRequiredFeatures.WasPassed()) {
+    const Sequence<JS::Value>& arr = (aOptions.mRequiredFeatures.Value());
+    for (const JS::Value& val : arr) {
+      if (!val.isNull() && !val.isUndefined()) {
+        bool bFound = false;
+        JS::RootedValue v(aCx, val);
+        int index = 0;
+        if (FindEnumStringIndex<false>(
+                callCx, v, XRReferenceSpaceTypeValues::strings,
+                "XRReferenceSpaceType", "Argument 2 of XR.requestSession",
+                &index)) {
+          if (index >= 0) {
+            requiredReferenceSpaceTypes.AppendElement(
+                static_cast<XRReferenceSpaceType>(index));
+            bFound = true;
+          }
+        }
+        if (!bFound) {
+          promise->MaybeRejectWithNotSupportedError(
+              "A required feature for the XRSession is not available.");
+          return promise.forget();
+        }
+      }
+    }
+  }
+
+  if (aOptions.mOptionalFeatures.WasPassed()) {
+    const Sequence<JS::Value>& arr = (aOptions.mOptionalFeatures.Value());
+    for (const JS::Value& val : arr) {
+      if (!val.isNull() && !val.isUndefined()) {
+        JS::RootedValue v(aCx, val);
+        int index = 0;
+        if (FindEnumStringIndex<false>(
+                callCx, v, XRReferenceSpaceTypeValues::strings,
+                "XRReferenceSpaceType", "Argument 2 of XR.requestSession",
+                &index)) {
+          if (index >= 0) {
+            optionalReferenceSpaceTypes.AppendElement(
+                static_cast<XRReferenceSpaceType>(index));
+          }
+        }
+      }
+    }
+  }
+
+  if (immersive) {
+    if (mPendingImmersiveSession || mActiveImmersiveSession) {
+      promise->MaybeRejectWithInvalidStateError(
+          "There can only be one immersive XRSession.");
+      return promise.forget();
+    }
+    mPendingImmersiveSession = true;
+  }
+
+  bool isChromeSession = aCallerType == CallerType::System;
+  uint32_t presentationGroup =
+      isChromeSession ? gfx::kVRGroupChrome : gfx::kVRGroupContent;
+  RefPtr<RequestSessionRequest> request = new RequestSessionRequest(
+      aMode, presentationGroup, promise, requiredReferenceSpaceTypes,
+      optionalReferenceSpaceTypes);
+  if (request->WantsHardware()) {
+    QueueSessionRequestWithEnumeration(request);
+  } else {
+    QueueSessionRequestWithoutEnumeration(request);
+  }
+
+  return promise.forget();
+}
+
+void XRSystem::QueueSessionRequestWithEnumeration(
+    RequestSessionRequest* aRequest) {
+  MOZ_ASSERT(aRequest->WantsHardware());
+  mRequestSessionRequestsWaitingForRuntimeDetection.AppendElement(aRequest);
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  vm->DetectRuntimes();
+}
+
+void XRSystem::QueueSessionRequestWithoutEnumeration(
+    RequestSessionRequest* aRequest) {
+  MOZ_ASSERT(!aRequest->NeedsHardware());
+  mRequestSessionRequestsWithoutHardware.AppendElement(aRequest);
+
+  ResolveSessionRequestsWithoutHardware();
+}
+
+bool XRSystem::CancelHardwareRequest(RequestSessionRequest* aRequest) {
+  if (!aRequest->NeedsHardware()) {
+    // If hardware access was an optional requirement and the user
+    // opted not to provide access, queue the request
+    // to be resolved without hardware.
+    QueueSessionRequestWithoutEnumeration(aRequest);
+    return false;
+  }
+
+  if (aRequest->IsImmersive()) {
+    mPendingImmersiveSession = false;
+  }
+  return true;
+}
+
+bool XRSystem::OnXRPermissionRequestAllow() {
+  if (!gfx::VRManagerChild::IsCreated()) {
+    // It's possible that this callback returns after
+    // we have already started shutting down.
+    return false;
+  }
+  if (!mEnumerationInFlight) {
+    mEnumerationInFlight = true;
+    gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+    Unused << vm->EnumerateVRDisplays();
+  }
+  return mEnumerationInFlight ||
+         !mRequestSessionRequestsWaitingForEnumeration.IsEmpty();
+}
+
+void XRSystem::OnXRPermissionRequestCancel() {
+  nsTArray<RefPtr<RequestSessionRequest>> requestSessionRequests(
+      std::move(mRequestSessionRequestsWaitingForEnumeration));
+  for (RefPtr<RequestSessionRequest>& request : requestSessionRequests) {
+    if (CancelHardwareRequest(request)) {
+      request->mPromise->MaybeRejectWithSecurityError(
+          "A device supporting the requested session "
+          "configuration could not be found.");
+    }
+  }
+}
+
+bool XRSystem::FeaturePolicyBlocked() const {
+  nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(GetOwner());
+  if (!win) {
+    return true;
+  }
+  RefPtr<XRPermissionRequest> request =
+      new XRPermissionRequest(win, win->WindowID());
+  return !(request->CheckPermissionDelegate());
+}
+
+bool XRSystem::HasActiveImmersiveSession() const {
+  return mActiveImmersiveSession;
+}
+
+void XRSystem::ResolveSessionRequestsWithoutHardware() {
+  // Resolve promises returned by RequestSession
+  nsTArray<RefPtr<gfx::VRDisplayClient>> displays;
+  // Try resolving support without a device, for inline sessions.
+  displays.AppendElement(nullptr);
+
+  nsTArray<RefPtr<RequestSessionRequest>> requestSessionRequests(
+      std::move(mRequestSessionRequestsWithoutHardware));
+
+  ResolveSessionRequests(requestSessionRequests, displays);
+}
+
+void XRSystem::NotifyEnumerationCompleted() {
+  // Enumeration has completed.
+  mEnumerationInFlight = false;
+
+  if (!gfx::VRManagerChild::IsCreated()) {
+    // It's possible that this callback returns after
+    // we have already started shutting down.
+    return;
+  }
+
+  // Resolve promises returned by RequestSession
+  nsTArray<RefPtr<gfx::VRDisplayClient>> displays;
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  vm->GetVRDisplays(displays);
+
+  nsTArray<RefPtr<RequestSessionRequest>> requestSessionRequests(
+      std::move(mRequestSessionRequestsWaitingForEnumeration));
+
+  ResolveSessionRequests(requestSessionRequests, displays);
+}
+
+void XRSystem::ResolveSessionRequests(
+    nsTArray<RefPtr<RequestSessionRequest>>& aRequests,
+    const nsTArray<RefPtr<gfx::VRDisplayClient>>& aDisplays) {
+  for (RefPtr<RequestSessionRequest>& request : aRequests) {
+    RefPtr<XRSession> session;
+    if (request->IsImmersive()) {
+      mPendingImmersiveSession = false;
+    }
+    // Select an XR device
+    for (const RefPtr<gfx::VRDisplayClient>& display : aDisplays) {
+      nsTArray<XRReferenceSpaceType> enabledReferenceSpaceTypes;
+      if (request->ResolveSupport(display, enabledReferenceSpaceTypes)) {
+        if (request->IsImmersive()) {
+          session = XRSession::CreateImmersiveSession(
+              GetOwner(), this, display, request->GetPresentationGroup(),
+              enabledReferenceSpaceTypes);
+          mActiveImmersiveSession = session;
+        } else {
+          session = XRSession::CreateInlineSession(GetOwner(), this,
+                                                   enabledReferenceSpaceTypes);
+          mInlineSessions.AppendElement(session);
+        }
+        request->mPromise->MaybeResolve(session);
+        break;
+      }
+    }
+    if (!session) {
+      request->mPromise->MaybeRejectWithNotSupportedError(
+          "A device supporting the required XRSession configuration "
+          "could not be found.");
+    }
+  }
+}
+
+void XRSystem::NotifyDetectRuntimesCompleted() {
+  ResolveIsSessionSupportedRequests();
+  if (!mRequestSessionRequestsWaitingForRuntimeDetection.IsEmpty()) {
+    ProcessSessionRequestsWaitingForRuntimeDetection();
+  }
+}
+
+void XRSystem::ResolveIsSessionSupportedRequests() {
+  // Resolve promises returned by IsSessionSupported
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+  nsTArray<RefPtr<IsSessionSupportedRequest>> isSessionSupportedRequests(
+      std::move(mIsSessionSupportedRequests));
+  bool featurePolicyBlocked = FeaturePolicyBlocked();
+
+  for (RefPtr<IsSessionSupportedRequest>& request :
+       isSessionSupportedRequests) {
+    if (featurePolicyBlocked) {
+      request->mPromise->MaybeRejectWithSecurityError(
+          "The xr-spatial-tracking feature policy is required.");
+      continue;
+    }
+
+    bool supported = false;
+    switch (request->GetSessionMode()) {
+      case XRSessionMode::Immersive_vr:
+        supported = vm->RuntimeSupportsVR();
+        break;
+      case XRSessionMode::Immersive_ar:
+        supported = vm->RuntimeSupportsAR();
+        break;
+      default:
+        break;
+    }
+    request->mPromise->MaybeResolve(supported);
+  }
+}
+
+void XRSystem::ProcessSessionRequestsWaitingForRuntimeDetection() {
+  bool alreadyRequestedPermission =
+      !mRequestSessionRequestsWaitingForEnumeration.IsEmpty();
+  bool featurePolicyBlocked = FeaturePolicyBlocked();
+  gfx::VRManagerChild* vm = gfx::VRManagerChild::Get();
+
+  nsTArray<RefPtr<RequestSessionRequest>> sessionRequests(
+      std::move(mRequestSessionRequestsWaitingForRuntimeDetection));
+
+  for (RefPtr<RequestSessionRequest>& request : sessionRequests) {
+    bool compatibleRuntime = false;
+    switch (request->GetSessionMode()) {
+      case XRSessionMode::Immersive_vr:
+        compatibleRuntime = vm->RuntimeSupportsVR();
+        break;
+      case XRSessionMode::Immersive_ar:
+        compatibleRuntime = vm->RuntimeSupportsAR();
+        break;
+      case XRSessionMode::Inline:
+        compatibleRuntime = vm->RuntimeSupportsInline();
+        break;
+      default:
+        break;
+    }
+    if (!compatibleRuntime) {
+      // If none of the requested sessions are supported by a
+      // runtime, early exit without showing a permission prompt.
+      if (CancelHardwareRequest(request)) {
+        request->mPromise->MaybeRejectWithNotSupportedError(
+            "A device supporting the required XRSession configuration "
+            "could not be found.");
+      }
+      continue;
+    }
+    if (featurePolicyBlocked) {
+      // Don't show a permission prompt if blocked by feature policy.
+      if (CancelHardwareRequest(request)) {
+        request->mPromise->MaybeRejectWithSecurityError(
+            "The xr-spatial-tracking feature policy is required.");
+      }
+      continue;
+    }
+    // To continue evaluating this request, it must wait for hardware
+    // enumeration and permission request.
+    mRequestSessionRequestsWaitingForEnumeration.AppendElement(request);
+  }
+
+  if (!mRequestSessionRequestsWaitingForEnumeration.IsEmpty() &&
+      !alreadyRequestedPermission) {
+    /**
+     * Inline sessions will require only a user gesture
+     * and should not trigger XR permission UI.
+     * This is not a problem currently, as the only platforms
+     * allowing xr-spatial-tracking for inline sessions do not
+     * present a modal XR permission UI. (eg. Android Firefox Reality)
+     */
+    nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(GetOwner());
+    win->RequestXRPermission();
+  }
+}
+
+void XRSystem::NotifyVRDisplayMounted(uint32_t aDisplayID) {}
+void XRSystem::NotifyVRDisplayUnmounted(uint32_t aDisplayID) {}
+
+void XRSystem::NotifyVRDisplayConnect(uint32_t aDisplayID) {
+  DispatchTrustedEvent(u"devicechange"_ns);
+}
+
+void XRSystem::NotifyVRDisplayDisconnect(uint32_t aDisplayID) {
+  DispatchTrustedEvent(u"devicechange"_ns);
+}
+
+void XRSystem::NotifyVRDisplayPresentChange(uint32_t aDisplayID) {}
+void XRSystem::NotifyPresentationGenerationChanged(uint32_t aDisplayID) {
+  if (mActiveImmersiveSession) {
+    mActiveImmersiveSession->ExitPresent();
+  }
+}
+bool XRSystem::GetStopActivityStatus() const { return true; }
+
+RequestSessionRequest::RequestSessionRequest(
+    XRSessionMode aSessionMode, uint32_t aPresentationGroup, Promise* aPromise,
+    const nsTArray<XRReferenceSpaceType>& aRequiredReferenceSpaceTypes,
+    const nsTArray<XRReferenceSpaceType>& aOptionalReferenceSpaceTypes)
+    : mPromise(aPromise),
+      mSessionMode(aSessionMode),
+      mPresentationGroup(aPresentationGroup),
+      mRequiredReferenceSpaceTypes(aRequiredReferenceSpaceTypes.Clone()),
+      mOptionalReferenceSpaceTypes(aOptionalReferenceSpaceTypes.Clone()) {}
+
+bool RequestSessionRequest::ResolveSupport(
+    const gfx::VRDisplayClient* aDisplay,
+    nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes) const {
+  if (aDisplay) {
+    if (!aDisplay->GetIsConnected()) {
+      return false;
+    }
+    if ((aDisplay->GetDisplayInfo().GetPresentingGroups() &
+         mPresentationGroup) != 0) {
+      return false;
+    }
+
+    const gfx::VRDisplayInfo& info = aDisplay->GetDisplayInfo();
+    switch (mSessionMode) {
+      case XRSessionMode::Inline:
+        if (!bool(info.mDisplayState.capabilityFlags &
+                  gfx::VRDisplayCapabilityFlags::Cap_Inline)) {
+          return false;
+        }
+        break;
+      case XRSessionMode::Immersive_vr:
+        if (!bool(info.mDisplayState.capabilityFlags &
+                  gfx::VRDisplayCapabilityFlags::Cap_ImmersiveVR)) {
+          return false;
+        }
+        break;
+      case XRSessionMode::Immersive_ar:
+        if (!bool(info.mDisplayState.capabilityFlags &
+                  gfx::VRDisplayCapabilityFlags::Cap_ImmersiveAR)) {
+          return false;
+        }
+        break;
+      default:
+        break;
+    }
+  } else if (mSessionMode != XRSessionMode::Inline) {
+    // If we don't have a device, we can only support inline sessions
+    return false;
+  }
+
+  // All sessions support XRReferenceSpaceType::Viewer by default
+  aEnabledReferenceSpaceTypes.AppendElement(XRReferenceSpaceType::Viewer);
+
+  // Immersive sessions support XRReferenceSpaceType::Local by default
+  if (IsImmersive()) {
+    aEnabledReferenceSpaceTypes.AppendElement(XRReferenceSpaceType::Local);
+  }
+
+  for (XRReferenceSpaceType type : mRequiredReferenceSpaceTypes) {
+    if (aDisplay) {
+      if (!aDisplay->IsReferenceSpaceTypeSupported(type)) {
+        return false;
+      }
+    } else if (type != XRReferenceSpaceType::Viewer) {
+      // If we don't have a device, We only support
+      // XRReferenceSpaceType::Viewer
+      return false;
+    }
+    if (!aEnabledReferenceSpaceTypes.Contains(type)) {
+      aEnabledReferenceSpaceTypes.AppendElement(type);
+    }
+  }
+  if (aDisplay) {
+    for (XRReferenceSpaceType type : mOptionalReferenceSpaceTypes) {
+      if (aDisplay->IsReferenceSpaceTypeSupported(type) &&
+          !aEnabledReferenceSpaceTypes.Contains(type)) {
+        aEnabledReferenceSpaceTypes.AppendElement(type);
+      }
+    }
+  }
+  return true;
+}
+
+bool RequestSessionRequest::IsImmersive() const {
+  return (mSessionMode == XRSessionMode::Immersive_vr ||
+          mSessionMode == XRSessionMode::Immersive_ar);
+}
+
+bool RequestSessionRequest::WantsHardware() const {
+  for (XRReferenceSpaceType type : mOptionalReferenceSpaceTypes) {
+    // Any XRReferenceSpaceType other than Viewer requires hardware
+    if (type != XRReferenceSpaceType::Viewer) {
+      return true;
+    }
+  }
+  return NeedsHardware();
+}
+
+bool RequestSessionRequest::NeedsHardware() const {
+  for (XRReferenceSpaceType type : mRequiredReferenceSpaceTypes) {
+    // Any XRReferenceSpaceType other than Viewer requires hardware
+    if (type != XRReferenceSpaceType::Viewer) {
+      return true;
+    }
+  }
+  return false;
+}
+
+XRSessionMode RequestSessionRequest::GetSessionMode() const {
+  return mSessionMode;
+}
+
+uint32_t RequestSessionRequest::GetPresentationGroup() const {
+  return mPresentationGroup;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// IsSessionSupportedRequest cycle collection
+NS_IMPL_CYCLE_COLLECTION(IsSessionSupportedRequest, mPromise)
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(IsSessionSupportedRequest, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(IsSessionSupportedRequest, Release)
+
+XRSessionMode IsSessionSupportedRequest::GetSessionMode() const {
+  return mSessionMode;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// XRRequestSessionPermissionRequest cycle collection
+NS_IMPL_CYCLE_COLLECTION_INHERITED(XRRequestSessionPermissionRequest,
+                                   ContentPermissionRequestBase)
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(
+    XRRequestSessionPermissionRequest, ContentPermissionRequestBase)
+
+XRRequestSessionPermissionRequest::XRRequestSessionPermissionRequest(
+    nsPIDOMWindowInner* aWindow, nsIPrincipal* aNodePrincipal,
+    AllowCallback&& aAllowCallback,
+    AllowAnySiteCallback&& aAllowAnySiteCallback,
+    CancelCallback&& aCancelCallback)
+    : ContentPermissionRequestBase(aNodePrincipal, aWindow, "dom.xr"_ns,
+                                   "xr"_ns),
+      mAllowCallback(std::move(aAllowCallback)),
+      mAllowAnySiteCallback(std::move(aAllowAnySiteCallback)),
+      mCancelCallback(std::move(aCancelCallback)),
+      mCallbackCalled(false) {
+  mPermissionRequests.AppendElement(
+      PermissionRequest(mType, nsTArray<nsString>()));
+}
+
+XRRequestSessionPermissionRequest::~XRRequestSessionPermissionRequest() {
+  Cancel();
+}
+
+NS_IMETHODIMP
+XRRequestSessionPermissionRequest::Cancel() {
+  if (!mCallbackCalled) {
+    mCallbackCalled = true;
+    mCancelCallback();
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+XRRequestSessionPermissionRequest::Allow(JS::HandleValue aChoices) {
+  nsTArray<PermissionChoice> choices;
+  nsresult rv = TranslateChoices(aChoices, mPermissionRequests, choices);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+
+  // There is no support to allow grants automatically from the prompting code
+  // path.
+
+  if (!mCallbackCalled) {
+    mCallbackCalled = true;
+    if (choices.Length() == 1 &&
+        choices[0].choice().EqualsLiteral("allow-on-any-site")) {
+      mAllowAnySiteCallback();
+    } else if (choices.Length() == 1 &&
+               choices[0].choice().EqualsLiteral("allow")) {
+      mAllowCallback();
+    }
+  }
+  return NS_OK;
+}
+
+already_AddRefed<XRRequestSessionPermissionRequest>
+XRRequestSessionPermissionRequest::Create(
+    nsPIDOMWindowInner* aWindow, AllowCallback&& aAllowCallback,
+    AllowAnySiteCallback&& aAllowAnySiteCallback,
+    CancelCallback&& aCancelCallback) {
+  if (!aWindow) {
+    return nullptr;
+  }
+  nsGlobalWindowInner* win = nsGlobalWindowInner::Cast(aWindow);
+  if (!win->GetPrincipal()) {
+    return nullptr;
+  }
+  RefPtr<XRRequestSessionPermissionRequest> request =
+      new XRRequestSessionPermissionRequest(
+          aWindow, win->GetPrincipal(), std::move(aAllowCallback),
+          std::move(aAllowAnySiteCallback), std::move(aCancelCallback));
+  return request.forget();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// RequestSessionRequest cycle collection
+NS_IMPL_CYCLE_COLLECTION(RequestSessionRequest, mPromise)
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(RequestSessionRequest, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(RequestSessionRequest, Release)
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRSystem.h b/dom/vr/XRSystem.h
new file mode 100644
index 0000000000..2fae6a6ce1
--- /dev/null
+++ b/dom/vr/XRSystem.h
@@ -0,0 +1,176 @@
+/* -*- 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_XRsystem_h_
+#define mozilla_dom_XRsystem_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "nsContentPermissionHelper.h"
+#include "VRManagerChild.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+struct XRSessionCreationOptions;
+
+class IsSessionSupportedRequest {
+ public:
+  IsSessionSupportedRequest(XRSessionMode aSessionMode, Promise* aPromise)
+      : mPromise(aPromise), mSessionMode(aSessionMode) {}
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(IsSessionSupportedRequest)
+  NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(IsSessionSupportedRequest)
+
+  RefPtr<Promise> mPromise;
+  XRSessionMode GetSessionMode() const;
+
+ private:
+  ~IsSessionSupportedRequest() = default;
+  XRSessionMode mSessionMode;
+};
+
+class RequestSessionRequest {
+ public:
+  RequestSessionRequest(
+      XRSessionMode aSessionMode, uint32_t aPresentationGroup,
+      Promise* aPromise,
+      const nsTArray<XRReferenceSpaceType>& aRequiredReferenceSpaceTypes,
+      const nsTArray<XRReferenceSpaceType>& aOptionalReferenceSpaceTypes);
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(RequestSessionRequest)
+  NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(RequestSessionRequest)
+  RefPtr<Promise> mPromise;
+
+  bool ResolveSupport(
+      const gfx::VRDisplayClient* aDisplay,
+      nsTArray<XRReferenceSpaceType>& aEnabledReferenceSpaceTypes) const;
+  bool IsImmersive() const;
+  bool WantsHardware() const;
+  bool NeedsHardware() const;
+  XRSessionMode GetSessionMode() const;
+  uint32_t GetPresentationGroup() const;
+
+ private:
+  ~RequestSessionRequest() = default;
+  XRSessionMode mSessionMode;
+  uint32_t mPresentationGroup;
+  nsTArray<XRReferenceSpaceType> mRequiredReferenceSpaceTypes;
+  nsTArray<XRReferenceSpaceType> mOptionalReferenceSpaceTypes;
+};
+
+class XRRequestSessionPermissionRequest final
+    : public ContentPermissionRequestBase {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XRRequestSessionPermissionRequest,
+                                           ContentPermissionRequestBase)
+
+  // nsIContentPermissionRequest
+  NS_IMETHOD Cancel(void) override;
+  NS_IMETHOD Allow(JS::HandleValue choices) override;
+
+  typedef std::function<void()> AllowCallback;
+  typedef std::function<void()> AllowAnySiteCallback;
+  typedef std::function<void()> CancelCallback;
+
+  static already_AddRefed<XRRequestSessionPermissionRequest> Create(
+      nsPIDOMWindowInner* aWindow, AllowCallback&& aAllowCallback,
+      AllowAnySiteCallback&& aAllowAnySiteCallback,
+      CancelCallback&& aCancelCallback);
+
+  typedef MozPromise<bool, bool, true> AutoGrantDelayPromise;
+  RefPtr<AutoGrantDelayPromise> MaybeDelayAutomaticGrants();
+
+ private:
+  XRRequestSessionPermissionRequest(
+      nsPIDOMWindowInner* aWindow, nsIPrincipal* aNodePrincipal,
+      AllowCallback&& aAllowCallback,
+      AllowAnySiteCallback&& aAllowAnySiteCallback,
+      CancelCallback&& aCancelCallback);
+  ~XRRequestSessionPermissionRequest();
+
+  AllowCallback mAllowCallback;
+  AllowAnySiteCallback mAllowAnySiteCallback;
+  CancelCallback mCancelCallback;
+  nsTArray<PermissionRequest> mPermissionRequests;
+  bool mCallbackCalled;
+};
+
+class XRSystem final : public DOMEventTargetHelper,
+                       public gfx::VRManagerEventObserver {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XRSystem, DOMEventTargetHelper)
+
+  void Shutdown();
+  void SessionEnded(XRSession* aSession);
+  bool FeaturePolicyBlocked() const;
+  bool OnXRPermissionRequestAllow();
+  void OnXRPermissionRequestCancel();
+  bool HasActiveImmersiveSession() const;
+
+  // WebIDL Boilerplate
+  static already_AddRefed<XRSystem> Create(nsPIDOMWindowInner* aWindow);
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  already_AddRefed<Promise> IsSessionSupported(XRSessionMode aMode,
+                                               ErrorResult& aRv);
+  already_AddRefed<Promise> RequestSession(JSContext* aCx, XRSessionMode aMode,
+                                           const XRSessionInit& aOptions,
+                                           CallerType aCallerType,
+                                           ErrorResult& aRv);
+  IMPL_EVENT_HANDLER(devicechange);
+
+  // VRManagerEventObserver interface
+  void NotifyVRDisplayMounted(uint32_t aDisplayID) override;
+  void NotifyVRDisplayUnmounted(uint32_t aDisplayID) override;
+  void NotifyVRDisplayConnect(uint32_t aDisplayID) override;
+  void NotifyVRDisplayDisconnect(uint32_t aDisplayID) override;
+  void NotifyVRDisplayPresentChange(uint32_t aDisplayID) override;
+  void NotifyPresentationGenerationChanged(uint32_t aDisplayID) override;
+  void NotifyEnumerationCompleted() override;
+  void NotifyDetectRuntimesCompleted() override;
+  bool GetStopActivityStatus() const override;
+
+ private:
+  explicit XRSystem(nsPIDOMWindowInner* aWindow);
+  virtual ~XRSystem() = default;
+  void ResolveIsSessionSupportedRequests();
+  void ProcessSessionRequestsWaitingForRuntimeDetection();
+  bool CancelHardwareRequest(RequestSessionRequest* aRequest);
+  void QueueSessionRequestWithEnumeration(RequestSessionRequest* aRequest);
+  void QueueSessionRequestWithoutEnumeration(RequestSessionRequest* aRequest);
+  void ResolveSessionRequestsWithoutHardware();
+  void ResolveSessionRequests(
+      nsTArray<RefPtr<RequestSessionRequest>>& aRequests,
+      const nsTArray<RefPtr<gfx::VRDisplayClient>>& aDisplays);
+
+  bool mShuttingDown;
+  // https://immersive-web.github.io/webxr/#pending-immersive-session
+  bool mPendingImmersiveSession;
+  // https://immersive-web.github.io/webxr/#active-immersive-session
+  RefPtr<XRSession> mActiveImmersiveSession;
+  // https://immersive-web.github.io/webxr/#list-of-inline-sessions
+  nsTArray<RefPtr<XRSession>> mInlineSessions;
+
+  bool mEnumerationInFlight;
+
+  nsTArray<RefPtr<IsSessionSupportedRequest>> mIsSessionSupportedRequests;
+  nsTArray<RefPtr<RequestSessionRequest>>
+      mRequestSessionRequestsWithoutHardware;
+  nsTArray<RefPtr<RequestSessionRequest>>
+      mRequestSessionRequestsWaitingForRuntimeDetection;
+  nsTArray<RefPtr<RequestSessionRequest>>
+      mRequestSessionRequestsWaitingForEnumeration;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRsystem_h_
diff --git a/dom/vr/XRView.cpp b/dom/vr/XRView.cpp
new file mode 100644
index 0000000000..10c919b081
--- /dev/null
+++ b/dom/vr/XRView.cpp
@@ -0,0 +1,97 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRView.h"
+
+#include "mozilla/HoldDropJSObjects.h"
+#include "mozilla/dom/XRRigidTransform.h"
+#include "mozilla/dom/Pose.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRView)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(XRView)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent, mTransform)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+  tmp->mJSProjectionMatrix = nullptr;
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(XRView)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent, mTransform)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(XRView)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mJSProjectionMatrix)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(XRView, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(XRView, Release)
+
+XRView::XRView(nsISupports* aParent, const XREye& aEye)
+    : mParent(aParent),
+      mEye(aEye),
+      mPosition(gfx::PointDouble3D()),
+      mOrientation(gfx::QuaternionDouble()),
+      mJSProjectionMatrix(nullptr) {
+  mozilla::HoldJSObjects(this);
+}
+
+XRView::~XRView() { mozilla::DropJSObjects(this); }
+
+JSObject* XRView::WrapObject(JSContext* aCx,
+                             JS::Handle<JSObject*> aGivenProto) {
+  return XRView_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+void XRView::Update(const gfx::PointDouble3D& aPosition,
+                    const gfx::QuaternionDouble& aOrientation,
+                    const gfx::Matrix4x4& aProjectionMatrix) {
+  mPosition = aPosition;
+  mOrientation = aOrientation;
+  mProjectionMatrix = aProjectionMatrix;
+  if (mTransform) {
+    mTransform->Update(aPosition, aOrientation);
+  }
+  if (aProjectionMatrix != mProjectionMatrix) {
+    mProjectionNeedsUpdate = true;
+    mProjectionMatrix = aProjectionMatrix;
+  }
+}
+
+XREye XRView::Eye() const { return mEye; }
+
+void XRView::GetProjectionMatrix(JSContext* aCx,
+                                 JS::MutableHandle<JSObject*> aRetval,
+                                 ErrorResult& aRv) {
+  if (!mJSProjectionMatrix || mProjectionNeedsUpdate) {
+    mProjectionNeedsUpdate = false;
+    gfx::Matrix4x4 mat;
+
+    Pose::SetFloat32Array(aCx, this, aRetval, mJSProjectionMatrix,
+                          mProjectionMatrix.components, 16, aRv);
+    if (!mJSProjectionMatrix) {
+      return;
+    }
+  }
+  if (mJSProjectionMatrix) {
+    JS::ExposeObjectToActiveJS(mJSProjectionMatrix);
+  }
+  aRetval.set(mJSProjectionMatrix);
+}
+
+already_AddRefed<XRRigidTransform> XRView::GetTransform(ErrorResult& aRv) {
+  if (!mTransform) {
+    mTransform = new XRRigidTransform(mParent, mPosition, mOrientation);
+  }
+  RefPtr<XRRigidTransform> transform = mTransform;
+  return transform.forget();
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRView.h b/dom/vr/XRView.h
new file mode 100644
index 0000000000..7cc4f1954b
--- /dev/null
+++ b/dom/vr/XRView.h
@@ -0,0 +1,58 @@
+/* -*- 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_XRView_h_
+#define mozilla_dom_XRView_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+enum class XREye : uint8_t;
+class XRRigidTransform;
+
+class XRView final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(XRView)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(XRView)
+
+  explicit XRView(nsISupports* aParent, const XREye& aEye);
+
+  void Update(const gfx::PointDouble3D& aPosition,
+              const gfx::QuaternionDouble& aOrientation,
+              const gfx::Matrix4x4& aProjectionMatrix);
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  XREye Eye() const;
+  void GetProjectionMatrix(JSContext* aCx, JS::MutableHandle<JSObject*> aRetval,
+                           ErrorResult& aRv);
+  already_AddRefed<XRRigidTransform> GetTransform(ErrorResult& aRv);
+
+ protected:
+  virtual ~XRView();
+
+  nsCOMPtr<nsISupports> mParent;
+  XREye mEye;
+  gfx::PointDouble3D mPosition;
+  gfx::QuaternionDouble mOrientation;
+  gfx::Matrix4x4 mProjectionMatrix;
+  JS::Heap<JSObject*> mJSProjectionMatrix;
+  bool mProjectionNeedsUpdate = true;
+  RefPtr<XRRigidTransform> mTransform;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRView_h_
diff --git a/dom/vr/XRViewerPose.cpp b/dom/vr/XRViewerPose.cpp
new file mode 100644
index 0000000000..5e1577ae50
--- /dev/null
+++ b/dom/vr/XRViewerPose.cpp
@@ -0,0 +1,46 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRViewerPose.h"
+#include "mozilla/dom/XRView.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(XRViewerPose)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(XRViewerPose, XRPose)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mViews)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(XRViewerPose, XRPose)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mViews)
+  // Don't need NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER because
+  // XRPose does it for us.
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(XRViewerPose, XRPose)
+
+XRViewerPose::XRViewerPose(nsISupports* aParent, XRRigidTransform* aTransform,
+                           bool aEmulatedPosition,
+                           const nsTArray<RefPtr<XRView>>& aViews)
+    : XRPose(aParent, aTransform, aEmulatedPosition), mViews(aViews.Clone()) {}
+
+JSObject* XRViewerPose::WrapObject(JSContext* aCx,
+                                   JS::Handle<JSObject*> aGivenProto) {
+  return XRViewerPose_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+RefPtr<XRView>& XRViewerPose::GetEye(int32_t aIndex) {
+  return mViews.ElementAt(aIndex);
+}
+
+void XRViewerPose::GetViews(nsTArray<RefPtr<XRView>>& aResult) {
+  aResult = mViews.Clone();
+}
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRViewerPose.h b/dom/vr/XRViewerPose.h
new file mode 100644
index 0000000000..b275367078
--- /dev/null
+++ b/dom/vr/XRViewerPose.h
@@ -0,0 +1,47 @@
+/* -*- 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_XRViewerPose_h_
+#define mozilla_dom_XRViewerPose_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "mozilla/dom/XRPose.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRRigidTransform;
+class XRView;
+
+class XRViewerPose final : public XRPose {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XRViewerPose, XRPose)
+
+  explicit XRViewerPose(nsISupports* aParent, XRRigidTransform* aTransform,
+                        bool aEmulatedPosition,
+                        const nsTArray<RefPtr<XRView>>& aViews);
+  RefPtr<XRView>& GetEye(int32_t aIndex);
+
+  // WebIDL Boilerplate
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  void GetViews(nsTArray<RefPtr<XRView>>& aResult);
+
+ protected:
+  virtual ~XRViewerPose() = default;
+  nsTArray<RefPtr<XRView>> mViews;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRViewerPose_h_
diff --git a/dom/vr/XRViewport.cpp b/dom/vr/XRViewport.cpp
new file mode 100644
index 0000000000..972a3d301e
--- /dev/null
+++ b/dom/vr/XRViewport.cpp
@@ -0,0 +1,33 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/XRViewport.h"
+
+namespace mozilla {
+namespace dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(XRViewport, mParent)
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(XRViewport, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(XRViewport, Release)
+
+XRViewport::XRViewport(nsISupports* aParent, const gfx::IntRect& aRect)
+    : mParent(aParent), mRect(aRect) {}
+
+JSObject* XRViewport::WrapObject(JSContext* aCx,
+                                 JS::Handle<JSObject*> aGivenProto) {
+  return XRViewport_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+int32_t XRViewport::X() { return mRect.X(); }
+
+int32_t XRViewport::Y() { return mRect.Y(); }
+
+int32_t XRViewport::Width() { return mRect.Width(); }
+
+int32_t XRViewport::Height() { return mRect.Height(); }
+
+}  // namespace dom
+}  // namespace mozilla
diff --git a/dom/vr/XRViewport.h b/dom/vr/XRViewport.h
new file mode 100644
index 0000000000..e158c574bd
--- /dev/null
+++ b/dom/vr/XRViewport.h
@@ -0,0 +1,49 @@
+/* -*- 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_XRViewport_h_
+#define mozilla_dom_XRViewport_h_
+
+#include "mozilla/DOMEventTargetHelper.h"
+#include "mozilla/dom/WebXRBinding.h"
+#include "mozilla/gfx/Rect.h"
+
+#include "gfxVR.h"
+
+namespace mozilla {
+namespace dom {
+
+class XRViewport final : public nsWrapperCache {
+ public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(XRViewport)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(XRViewport)
+
+  explicit XRViewport(nsISupports* aParent, const gfx::IntRect& aRect);
+
+  // WebIDL Boilerplate
+  nsISupports* GetParentObject() const { return mParent; }
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  // WebIDL Members
+  int32_t X();
+  int32_t Y();
+  int32_t Width();
+  int32_t Height();
+
+ protected:
+  virtual ~XRViewport() = default;
+
+  nsCOMPtr<nsISupports> mParent;
+
+ public:
+  gfx::IntRect mRect;
+};
+
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_XRViewport_h_
diff --git a/dom/vr/moz.build b/dom/vr/moz.build
new file mode 100644
index 0000000000..f0c6fc70c0
--- /dev/null
+++ b/dom/vr/moz.build
@@ -0,0 +1,67 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+with Files("**"):
+    BUG_COMPONENT = ("Core", "WebVR")
+
+EXPORTS.mozilla.dom += [
+    "VRDisplay.h",
+    "VRDisplayEvent.h",
+    "VREventObserver.h",
+    "VRServiceTest.h",
+    "XRBoundedReferenceSpace.h",
+    "XRFrame.h",
+    "XRInputSource.h",
+    "XRInputSourceArray.h",
+    "XRNativeOrigin.h",
+    "XRPermissionRequest.h",
+    "XRPose.h",
+    "XRReferenceSpace.h",
+    "XRRenderState.h",
+    "XRRigidTransform.h",
+    "XRSession.h",
+    "XRSpace.h",
+    "XRSystem.h",
+    "XRView.h",
+    "XRViewerPose.h",
+    "XRViewport.h",
+]
+
+UNIFIED_SOURCES = [
+    "VRDisplay.cpp",
+    "VRDisplayEvent.cpp",
+    "VREventObserver.cpp",
+    "VRServiceTest.cpp",
+    "XRBoundedReferenceSpace.cpp",
+    "XRFrame.cpp",
+    "XRInputSource.cpp",
+    "XRInputSourceArray.cpp",
+    "XRInputSpace.cpp",
+    "XRNativeOriginFixed.cpp",
+    "XRNativeOriginLocal.cpp",
+    "XRNativeOriginLocalFloor.cpp",
+    "XRNativeOriginTracker.cpp",
+    "XRNativeOriginViewer.cpp",
+    "XRPermissionRequest.cpp",
+    "XRPose.cpp",
+    "XRReferenceSpace.cpp",
+    "XRRenderState.cpp",
+    "XRRigidTransform.cpp",
+    "XRSession.cpp",
+    "XRSpace.cpp",
+    "XRSystem.cpp",
+    "XRView.cpp",
+    "XRViewerPose.cpp",
+    "XRViewport.cpp",
+]
+
+include("/ipc/chromium/chromium-config.mozbuild")
+
+FINAL_LIBRARY = "xul"
+LOCAL_INCLUDES += ["/dom/base"]
+
+MOCHITEST_MANIFESTS += ["test/mochitest/mochitest.ini"]
+REFTEST_MANIFESTS += ["test/reftest/reftest.list"]
diff --git a/dom/vr/test/crashtests/crashtests.list b/dom/vr/test/crashtests/crashtests.list
new file mode 100644
index 0000000000..1cc06896f8
--- /dev/null
+++ b/dom/vr/test/crashtests/crashtests.list
@@ -0,0 +1 @@
+pref(dom.vr.always_support_vr,true) load enumerate_vr_on_dying_window.html

diff --git a/dom/vr/test/crashtests/enumerate_vr_on_dying_window.html b/dom/vr/test/crashtests/enumerate_vr_on_dying_window.html
new file mode 100644
index 0000000000..2906faa79c
--- /dev/null
+++ b/dom/vr/test/crashtests/enumerate_vr_on_dying_window.html
@@ -0,0 +1,14 @@
+<html>
+<head>
+<script>
+window.onload = function(){
+  var frame = document.getElementById('test_iframe');
+  var win = frame.contentWindow;
+  frame.remove();
+  win.onvrdisplayactivate = function () {}
+};
+</script></head>
+<body>
+	<iframe id="test_iframe"></iframe>
+</body>
+</html>
diff --git a/dom/vr/test/mochitest/VRSimulationDriver.js b/dom/vr/test/mochitest/VRSimulationDriver.js
new file mode 100644
index 0000000000..5129485926
--- /dev/null
+++ b/dom/vr/test/mochitest/VRSimulationDriver.js
@@ -0,0 +1,95 @@
+var VRServiceTest;
+var vrMockDisplay;
+
+var VRSimulationDriver = (function() {
+  "use strict";
+
+  var AttachWebVRDisplay = function() {
+    if (vrMockDisplay) {
+      // Avoid creating multiple displays
+      return Promise.resolve(vrMockDisplay);
+    }
+    var promise = VRServiceTest.attachVRDisplay("VRDisplayTest");
+    promise.then(function(display) {
+      assert_true(display != null, "AttachWebVRDisplay should success.");
+      vrMockDisplay = display;
+    });
+
+    return promise;
+  };
+
+  var SetVRDisplayPose = function(
+    position,
+    linearVelocity,
+    linearAcceleration,
+    orientation,
+    angularVelocity,
+    angularAcceleration
+  ) {
+    vrMockDisplay.setPose(
+      position,
+      linearVelocity,
+      linearAcceleration,
+      orientation,
+      angularVelocity,
+      angularAcceleration
+    );
+  };
+
+  var SetEyeResolution = function(width, height) {
+    vrMockDisplay.setEyeResolution(width, height);
+  };
+
+  var SetEyeParameter = function(
+    eye,
+    offsetX,
+    offsetY,
+    offsetZ,
+    upDegree,
+    rightDegree,
+    downDegree,
+    leftDegree
+  ) {
+    vrMockDisplay.setEyeParameter(
+      eye,
+      offsetX,
+      offsetY,
+      offsetZ,
+      upDegree,
+      rightDegree,
+      downDegree,
+      leftDegree
+    );
+  };
+
+  var SetMountState = function(isMounted) {
+    vrMockDisplay.setMountState(isMounted);
+  };
+
+  var UpdateVRDisplay = function() {
+    vrMockDisplay.update();
+  };
+
+  var AttachVRController = function() {
+    var promise = VRServiceTest.attachVRController("VRControllerTest");
+    promise.then(function(controller) {
+      assert_true(controller != null, "AttachVRController should success.");
+    });
+
+    return promise;
+  };
+
+  var API = {
+    AttachWebVRDisplay,
+    SetVRDisplayPose,
+    SetEyeResolution,
+    SetEyeParameter,
+    SetMountState,
+    UpdateVRDisplay,
+    AttachVRController,
+
+    none: false,
+  };
+
+  return API;
+})();
diff --git a/dom/vr/test/mochitest/WebVRHelpers.js b/dom/vr/test/mochitest/WebVRHelpers.js
new file mode 100644
index 0000000000..a2037bf821
--- /dev/null
+++ b/dom/vr/test/mochitest/WebVRHelpers.js
@@ -0,0 +1,19 @@
+var WebVRHelpers = (function() {
+  "use strict";
+
+  var RequestPresentOnVRDisplay = function(vrDisplay, vrLayers, callback) {
+    if (callback) {
+      callback();
+    }
+
+    return vrDisplay.requestPresent(vrLayers);
+  };
+
+  var API = {
+    RequestPresentOnVRDisplay,
+
+    none: false,
+  };
+
+  return API;
+})();
diff --git a/dom/vr/test/mochitest/mochitest.ini b/dom/vr/test/mochitest/mochitest.ini
new file mode 100644
index 0000000000..87a4174a21
--- /dev/null
+++ b/dom/vr/test/mochitest/mochitest.ini
@@ -0,0 +1,31 @@
+# Please confirm there is no other VR display connected. Otherwise, VRPuppetDisplay can't be attached.
+[DEFAULT]
+support-files =
+  VRSimulationDriver.js
+  requestPresent.js
+  runVRTest.js
+  WebVRHelpers.js
+[test_vrController_displayId.html]
+# Enable Linux after Bug 1310655 # TIMED_OUT for Android.
+# skip-if = (os != "win" && release_or_beta) || (os == "android")
+# Dependencies for re-enabling these are tracked by meta bug 1555185.
+skip-if = true
+[test_vrDisplay_canvas2d.html]
+# skip-if = (os != "win" && release_or_beta) # Enable Linux after Bug 1310655
+# Dependencies for re-enabling these are tracked by meta bug 1555185.
+skip-if = true
+[test_vrDisplay_exitPresent.html]
+# skip-if = (os != "win" && release_or_beta) # Enable Linux after Bug 1310655
+# Dependencies for re-enabling these are tracked by meta bug 1555185.
+skip-if = true
+[test_vrDisplay_getFrameData.html]
+# Enable Linux after Bug 1310655, enable Android after Bug 1348246
+# skip-if = (os != "win" && release_or_beta) || (os == "android")
+# Dependencies for re-enabling these are tracked by meta bug 1555185.
+skip-if = true
+[test_vrDisplay_onvrdisplayconnect.html]
+skip-if = true
+[test_vrDisplay_onvrdisplaydeactivate_crosscontent.html]
+skip-if = true
+[test_vrDisplay_requestPresent.html]
+skip-if = true
diff --git a/dom/vr/test/mochitest/requestPresent.js b/dom/vr/test/mochitest/requestPresent.js
new file mode 100644
index 0000000000..a2f9dd4d11
--- /dev/null
+++ b/dom/vr/test/mochitest/requestPresent.js
@@ -0,0 +1,74 @@
+// requestPresent.js
+//
+// This file provides helpers for testing VRDisplay requestPresent.
+
+function attachVRDisplay(test) {
+  assert_equals(
+    typeof navigator.getVRDisplays,
+    "function",
+    "'navigator.getVRDisplays()' must be defined."
+  );
+  return VRSimulationDriver.AttachWebVRDisplay();
+}
+
+function setupVRDisplay(test) {
+  assert_equals(
+    typeof navigator.getVRDisplays,
+    "function",
+    "'navigator.getVRDisplays()' must be defined."
+  );
+  return VRSimulationDriver.AttachWebVRDisplay()
+    .then(() => {
+      return navigator.getVRDisplays();
+    })
+    .then(displays => {
+      assert_equals(
+        displays.length,
+        1,
+        "displays.length must be one after attach."
+      );
+      vrDisplay = displays[0];
+      return validateNewVRDisplay(test, vrDisplay);
+    });
+}
+
+// Validate the settings off a freshly created VRDisplay (prior to calling
+// requestPresent).
+function validateNewVRDisplay(test, display) {
+  assert_true(
+    display.capabilities.canPresent,
+    "display.capabilities.canPresent must always be true for HMDs."
+  );
+  assert_equals(
+    display.capabilities.maxLayers,
+    1,
+    "display.capabilities.maxLayers must always be 1 when display.capabilities.canPresent is true for current spec revision."
+  );
+  assert_false(
+    display.isPresenting,
+    "display.isPresenting must be false before calling requestPresent."
+  );
+  assert_equals(
+    display.getLayers().length,
+    0,
+    "display.getLayers() should have no layers if not presenting."
+  );
+  var promise = display.exitPresent();
+  return promise_rejects(test, null, promise);
+}
+
+// Validate the settings off a VRDisplay after requestPresent promise is
+// rejected or after exitPresent is fulfilled.
+function validateDisplayNotPresenting(test, display) {
+  assert_false(
+    display.isPresenting,
+    "display.isPresenting must be false if requestPresent is rejected or after exitPresent is fulfilled."
+  );
+  assert_equals(
+    display.getLayers().length,
+    0,
+    "display.getLayers() should have no layers if requestPresent is rejected  or after exitPresent is fulfilled."
+  );
+  var promise = display.exitPresent();
+  return promise_rejects(test, null, promise);
+}
diff --git a/dom/vr/test/mochitest/runVRTest.js b/dom/vr/test/mochitest/runVRTest.js
new file mode 100644
index 0000000000..d5a80853e0
--- /dev/null
+++ b/dom/vr/test/mochitest/runVRTest.js
@@ -0,0 +1,17 @@
+function runVRTest(callback) {
+  SpecialPowers.pushPrefEnv(
+    {
+      set: [
+        ["dom.vr.puppet.enabled", true],
+        ["dom.vr.require-gesture", false],
+        ["dom.vr.test.enabled", true],
+        ["dom.vr.display.enumerate.interval", 0],
+        ["dom.vr.controller.enumerate.interval", 0],
+      ],
+    },
+    () => {
+      VRServiceTest = navigator.requestVRServiceTest();
+      callback();
+    }
+  );
+}
diff --git a/dom/vr/test/mochitest/test_vrController_displayId.html b/dom/vr/test/mochitest/test_vrController_displayId.html
new file mode 100644
index 0000000000..e69e3920d2
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrController_displayId.html
@@ -0,0 +1,57 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>VRController DisplayId</title>
+    <meta name="timeout" content="long"/>
+    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="runVRTest.js"></script>
+  </head>
+  <body>
+    <script>
+      "use strict";
+      var vrDisplay;
+      var controllerCount = 0;
+
+      function addController() {
+        promise_test((test) => {
+          return VRSimulationDriver.AttachVRController().then((controller) => {
+            controller.newButtonEvent(0, true);
+          });
+        }, "Finish to add VRController.");
+      }
+
+      function listenControllerEvents() {
+        async_test(function(t) {
+          window.addEventListener("gamepadbuttondown", function(e) {
+              assert_equals(e.gamepad.displayId, vrDisplay.displayId, "gamepad.displayId should be equal to vrDisplay.");
+              assert_equals(e.gamepad.id, "Puppet Gamepad", "gamepad.id must be equal to 'Puppet Gamepad'.");
+              ++controllerCount;
+              if (controllerCount == 2) {
+                t.done();
+              }
+          });
+        }, "Finish to verify VRController.displayId.");
+      }
+
+      function startTest() {
+        promise_test((test) => {
+          listenControllerEvents();
+          return VRSimulationDriver.AttachWebVRDisplay().then(() => {
+            return navigator.getVRDisplays().then((displays) => {
+              vrDisplay = displays[0];
+              assert_equals(displays.length, 1, "displays.length must be one after attach.");
+              assert_equals(vrDisplay.displayName, "Puppet HMD", "display.displayName must be equal to 'Puppet HMD'.");
+              addController();
+              addController();
+            });
+          });
+        }, "Finish to add VRDisplay.");
+      }
+
+      runVRTest(startTest);
+    </script>
+  </body>
+</html>
diff --git a/dom/vr/test/mochitest/test_vrDisplay_canvas2d.html b/dom/vr/test/mochitest/test_vrDisplay_canvas2d.html
new file mode 100644
index 0000000000..4d20e21352
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrDisplay_canvas2d.html
@@ -0,0 +1,55 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>VRDisplay Canvas2D</title>
+    <meta name="timeout" content="long"/>
+    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="runVRTest.js"></script>
+  </head>
+  <body>
+    <script>
+      "use strict";
+      var vrDisplay;
+
+      function requestPresentTest() {
+        async_test(function (test) {
+          vrDisplay.requestAnimationFrame(callback);
+
+          function callback() {
+            vrDisplay.resetPose();
+            vrDisplay.getLayers();
+            vrDisplay.submitFrame();
+            vrDisplay.getEyeParameters("right");
+            test.done();
+          }
+        }, "Finish WebVR Canvas2D requestPresentTest.");
+      }
+
+      function startTest() {
+        promise_test((test) => {
+          var canvas = document.createElement('canvas');
+          (document.body || document.documentElement).appendChild(canvas);
+          var context = canvas.getContext('2d');
+          var img = document.createElement('img');
+          img.src = "data:image/gif;base64,R0lGODlhAQABAAAAACw=";
+
+          return VRSimulationDriver.AttachWebVRDisplay().then(() => {
+            return navigator.getVRDisplays().then((displays) => {
+              assert_equals(displays.length, 1, "displays.length must be one after attach.");
+              vrDisplay = displays[0];
+              var frameData = new VRFrameData();
+              return vrDisplay.requestPresent([{source: canvas}]).then(() => {
+                requestPresentTest();
+              });
+            });
+          });
+        }, "Finish running WebVR Canvas2D test.");
+      }
+
+      runVRTest(startTest);
+    </script>
+  </body>
+</html>
diff --git a/dom/vr/test/mochitest/test_vrDisplay_exitPresent.html b/dom/vr/test/mochitest/test_vrDisplay_exitPresent.html
new file mode 100644
index 0000000000..dc2c700723
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrDisplay_exitPresent.html
@@ -0,0 +1,51 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>VRDisplay ExitPresent</title>
+    <meta name="timeout" content="long"/>
+    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="runVRTest.js"></script>
+  </head>
+  <body>
+    <script>
+      function testExitPresentOnOtherIframe(content) {
+          return content.navigator.getVRDisplays().then((displays) => {
+            content.vrDisplay = displays[0];
+            return content.vrDisplay.exitPresent();
+        });
+      }
+      var initVRPresentation = function(content) {
+        return VRSimulationDriver.AttachWebVRDisplay().then(() => {
+          return content.navigator.getVRDisplays().then((displays) => {
+            content.vrDisplay = displays[0];
+            content.canvas = content.document.createElement("canvas");
+            content.canvas.id = "vrCanvas";
+            return content.vrDisplay.requestPresent([{source:content.canvas}]);
+          });
+        });
+      }
+      function startTest() {
+        var ifr1 = document.getElementById("iframe1");
+        var ifr2 = document.getElementById("iframe2");
+        var frame1 = ifr1.contentWindow;
+        var frame2 = ifr2.contentWindow;
+        promise_test((test) => {
+          return VRSimulationDriver.AttachWebVRDisplay().then(() => {
+            return initVRPresentation(frame1).then(() => {
+              promise_test((test) => {
+                return promise_rejects(test, null, testExitPresentOnOtherIframe(frame2));
+              }, "We cannot exit VR presentation established by another content, this promise is expected to be rejected.")
+            });
+          });
+        }, "Finish running WebVR exitPresent test.");
+      }
+      runVRTest(startTest);
+    </script>
+
+    <iframe id="iframe1"></iframe>
+    <iframe id="iframe2"></iframe>
+  </body>
+</html>
diff --git a/dom/vr/test/mochitest/test_vrDisplay_getFrameData.html b/dom/vr/test/mochitest/test_vrDisplay_getFrameData.html
new file mode 100644
index 0000000000..c8a986ae8e
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrDisplay_getFrameData.html
@@ -0,0 +1,148 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>VRDisplay GetFrameData</title>
+    <meta name="timeout" content="long"/>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="WebVRHelpers.js"></script>
+    <script src="requestPresent.js"></script>
+    <script src="runVRTest.js"></script>
+</head>
+<body id="body">
+    <canvas id="webglCanvas"></canvas>
+    <script>
+        "use strict";
+        var vrDisplay;
+        var vrRAF;
+        var canvas = document.getElementById('webglCanvas');
+        function startTest() {
+          promise_test((test) => {
+            return attachVRDisplay(test).then(() => {
+              VRSimulationDriver.SetEyeResolution(1332, 1586);
+              VRSimulationDriver.SetEyeParameter("left", -0.029, 0, 0, 41.65, 35.57, 48.00, 43.97);
+              VRSimulationDriver.SetEyeParameter("right", 0.029, 0, 0, 41.65, 43.97, 48.00, 35.57);
+              var poseOrient = new Float32Array([-0.188, -0.007, 0.045, -0.980]);
+              var posePos = new Float32Array([-0.161, 0.076, -0.250]);
+              var poseAngVel = new Float32Array([0.008, -0.002, -0.006]);
+              var poseAngAcc = new Float32Array([3.404, -1.469, -5.901]);
+              var poseLinVel = new Float32Array([0.001, -0.003, -0.002]);
+              var poseLinAcc = new Float32Array([0.007, 0.068, -0.052]);
+              VRSimulationDriver.SetVRDisplayPose(posePos, poseLinVel, poseLinAcc,
+                                                  poseOrient, poseAngVel, poseAngAcc);
+              VRSimulationDriver.UpdateVRDisplay();
+            }).then(() => {
+              return promise_test((test) => {
+                return setupVRDisplay(test).then(() => {
+                  return WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay,
+                                                                [{ source: canvas }]);
+                }).then(() => {
+                  assert_true(vrDisplay.isPresenting, "vrDisplay.isPresenting must be true if requestPresent is fulfilled.");
+                  assert_equals(vrDisplay.getLayers().length, 1, "vrDisplay.getLayers() should return one layer.");
+
+                  verifyFrameData();
+                })
+              }, "WebVR requestPresent fulfilled");
+            })
+          }, "Finish setting up VR test data.");
+
+          function verifyFrameData() {
+            async_test(function (test) {
+              navigator.getVRDisplays().then((displays) => {
+                assert_equals(displays.length, 1, "displays.length must be one after attach.");
+                vrDisplay = displays[0];
+                vrDisplay.requestAnimationFrame(callback);
+
+                function callback() {
+                  var frameData1 = new VRFrameData();
+                  vrDisplay.getFrameData(frameData1);
+
+                  // We insert a new frame to confirm we still can get
+                  // the same data as the last getter.
+                  insertNewFrameData();
+
+                  var frameData2 = new VRFrameData();
+                  vrDisplay.getFrameData(frameData2);
+
+                  assert_equals(frameData1.timestamp, frameData2.timestamp,
+                                "frameData.timestamp at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(frameData1.leftProjectionMatrix,
+                                                       frameData2.leftProjectionMatrix),
+                              "frameData.leftProjectionMatrix at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(frameData1.leftViewMatrix,
+                                                       frameData2.leftViewMatrix),
+                              "frameData.leftViewMatrix at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(frameData1.rightProjectionMatrix,
+                                                       frameData2.rightProjectionMatrix),
+                              "frameData.rightProjectionMatrix at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(frameData1.rightViewMatrix,
+                                                       frameData2.rightViewMatrix),
+                              "frameData.rightViewMatrix at a frame should be equal.");
+
+                  var pose1 = frameData1.pose;
+                  var pose2 = frameData2.pose;
+                  assert_true(checkValueInFloat32Array(pose1.position,
+                                                       pose2.position),
+                              "pose.position at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(pose1.linearVelocity,
+                                                       pose2.linearVelocity),
+                              "pose.linearVelocity at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(pose1.linearAcceleration,
+                                                       pose2.linearAcceleration),
+                              "pose.linearAcceleration at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(pose1.orientation,
+                                                       pose2.orientation),
+                              "pose.orientation at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(pose1.angularVelocity,
+                                                       pose2.angularVelocity),
+                              "pose.angularVelocity at a frame should be equal.");
+
+                  assert_true(checkValueInFloat32Array(pose1.angularAcceleration,
+                                                       pose2.angularAcceleration),
+                              "pose.angularAcceleration at a frame should be equal.");
+                  test.done();
+                }
+              });
+            }, "WebVR returns the same frameData within a frame fulfilled");
+          }
+
+          function insertNewFrameData() {
+            var poseOrient = new Float32Array([-0.208, -0.017, 0.055, -0.930]);
+            var posePos = new Float32Array([-0.261, 0.036, -0.150]);
+            var poseAngVel = new Float32Array([0.018, -0.001, -0.003]);
+            var poseAngAcc = new Float32Array([1.504, -1.339, -4.901]);
+            var poseLinVel = new Float32Array([0.002, -0.001, -0.003]);
+            var poseLinAcc = new Float32Array([0.017, 0.061, -0.022]);
+            VRSimulationDriver.SetVRDisplayPose(posePos, poseLinVel, poseLinAcc,
+                                                poseOrient, poseAngVel, poseAngAcc);
+            VRSimulationDriver.UpdateVRDisplay();
+          }
+
+          function checkValueInFloat32Array(array1, array2) {
+            if (array1.length != array2.length) {
+              return false;
+            }
+            var index = 0;
+            while (index < array2.length) {
+              if (array1[index] != array2[index]) {
+                return false;
+              }
+              ++index;
+            }
+            return true;
+          }
+        }
+
+        runVRTest(startTest);
+    </script>
+</body>
+</html>
diff --git a/dom/vr/test/mochitest/test_vrDisplay_onvrdisplayconnect.html b/dom/vr/test/mochitest/test_vrDisplay_onvrdisplayconnect.html
new file mode 100644
index 0000000000..e1912c7c41
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrDisplay_onvrdisplayconnect.html
@@ -0,0 +1,43 @@
+<html>
+  <head>
+    <title>VRDisplay onvrdisplayconnect test</title>
+    <meta name="timeout" content="long"/>
+    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="WebVRHelpers.js"></script>
+    <script src="requestPresent.js"></script>
+    <script src="runVRTest.js"></script>
+  </head>
+  <body>
+    <script>
+
+      function eventAfterConnectedTest() {
+        async_test(function (test) {
+          window.addEventListener("vrdisplayconnect", () => {
+            test.done();
+          });
+        }, "vrdisplayconnect should fire as soon as content listens for it, \
+            even if the VR display was already connected.");
+      }
+
+      function startTest() {
+        promise_test((test) => {
+          return attachVRDisplay(test).then(() => {
+            return promise_test((test) => {
+              return setupVRDisplay(test).then(() => {
+                VRSimulationDriver.UpdateVRDisplay();
+                eventAfterConnectedTest();
+                VRSimulationDriver.UpdateVRDisplay();
+              });
+            });
+          });
+        });
+      }
+
+      runVRTest(startTest);
+    </script>
+    <iframe id="iframe1"></iframe>
+  </body>
+</html>
diff --git a/dom/vr/test/mochitest/test_vrDisplay_onvrdisplaydeactivate_crosscontent.html b/dom/vr/test/mochitest/test_vrDisplay_onvrdisplaydeactivate_crosscontent.html
new file mode 100644
index 0000000000..6c58e5efd1
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrDisplay_onvrdisplaydeactivate_crosscontent.html
@@ -0,0 +1,54 @@
+<html>
+  <head>
+    <title>VRDisplay onvrdisplaydeactivate Crosscontent test</title>
+    <meta name="timeout" content="long"/>
+    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="WebVRHelpers.js"></script>
+    <script src="requestPresent.js"></script>
+    <script src="runVRTest.js"></script>
+  </head>
+  <body>
+    <canvas id="vrCanvas"></canvas>
+    <script>
+
+      function startTest() {
+        var canvas = document.getElementById("vrCanvas");
+        var iframe1 = document.getElementById("iframe1").contentWindow;
+        var t = async_test("vrdisplaydeactivate crosscontent test");
+
+        window.addEventListener("vrdisplaydeactivate", () => {
+          t.step(() => {
+            assert_true(vrDisplay.isPresenting,
+                        "VRDisplay should be still presenting now without being affected by the event.");
+            t.done();
+          });
+        });
+
+        iframe1.addEventListener("vrdisplaydeactivate", () => {
+          t.unreached_func("vrdisplaydeactivate should not be received by other iframe.");
+        });
+
+        promise_test((test) => {
+          return attachVRDisplay(test).then(() => {
+            return promise_test((test) => {
+              return setupVRDisplay(test).then(() => {
+                VRSimulationDriver.SetMountState(true);
+                VRSimulationDriver.UpdateVRDisplay();
+                return WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{source: canvas}]);
+              }).then(() => {
+                VRSimulationDriver.SetMountState(false);
+                VRSimulationDriver.UpdateVRDisplay();
+              });
+            });
+          });
+        });
+      }
+
+      runVRTest(startTest);
+    </script>
+    <iframe id="iframe1"></iframe>
+  </body>
+</html>
diff --git a/dom/vr/test/mochitest/test_vrDisplay_requestPresent.html b/dom/vr/test/mochitest/test_vrDisplay_requestPresent.html
new file mode 100644
index 0000000000..4d021b6e0f
--- /dev/null
+++ b/dom/vr/test/mochitest/test_vrDisplay_requestPresent.html
@@ -0,0 +1,130 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>VRDisplay RequestPresent</title>
+    <meta name="timeout" content="long"/>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="VRSimulationDriver.js"></script>
+    <script src="WebVRHelpers.js"></script>
+    <script src="requestPresent.js"></script>
+    <script src="runVRTest.js"></script>
+</head>
+<body id="body">
+    <canvas id="webglCanvas"></canvas>
+    <div id="testDiv"></div>
+    <script>
+        "use strict";
+        var vrDisplay;
+        var canvas = document.getElementById('webglCanvas');
+        var div = document.getElementById('testDiv');
+        function startTest() {
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              return promise_rejects(test, null, WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{}]));
+            }).then(() => {
+              return validateDisplayNotPresenting(test, vrDisplay);
+            });
+          }, "WebVR requestPresent rejected with empty frames");
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              return promise_rejects(test, null, WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: canvas, leftBounds: [0.0, 0.0] }]));
+            }).then(() => {
+              return validateDisplayNotPresenting(test, vrDisplay);
+            });
+          }, "WebVR requestPresent rejected with incorrect bounds (bounds arrays must be 0 or 4 long)");
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              return promise_rejects(test, null, WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: div }]));
+            }).then(() => {
+              return validateDisplayNotPresenting(test, vrDisplay);
+            });
+          }, "WebVR requestPresent rejected with invalid source (must be canvas element)");
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              return promise_rejects(test, null, WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: canvas, leftBounds: [div] }]));
+            }).then(() => {
+              return validateDisplayNotPresenting(test, vrDisplay);
+            });
+          }, "WebVR requestPresent rejected with invalid bounds data type (must be able to convert to float)");
+
+          const invalidBounds = [
+            [2.0, 0.0, 0.0, 0.0],
+            [0.0, 2.0, 0.0, 0.0],
+            [0.0, 0.0, 2.0, 0.0],
+            [0.0, 0.0, 0.0, 2.0],
+            [-1.0, 0.0, 0.0, 0.0],
+            [0.0, -1.0, 0.0, 0.0],
+            [0.0, 0.0, -1.0, 0.0],
+            [0.0, 0.0, 0.0, -1.0]];
+
+          invalidBounds.forEach((bound) => {
+            promise_test((test) => {
+              return setupVRDisplay(test).then(() => {
+                return promise_rejects(test, null, WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: canvas, leftBounds: bound }]));
+              }).then(() => {
+                return validateDisplayNotPresenting(test, vrDisplay);
+              });
+            }, "WebVR requestPresent rejected with bounds in invalid range: [" + bound + "]");
+          });
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              var promise = vrDisplay.requestPresent({ source: canvas });
+              return promise_rejects(test, null, promise);
+            }).then(() => {
+              return validateDisplayNotPresenting(test, vrDisplay);
+            });
+          }, "WebVR requestPresent rejected without user initiated action");
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              return promise_rejects(test, null, WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: canvas }, { source: canvas }]));
+            }).then(() => {
+              return validateDisplayNotPresenting(test, vrDisplay);
+            });
+          }, "WebVR requestPresent rejected with more frames than max layers");
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              function requestAgain() {
+                // Callback for immediate requestPresent call for further testing.
+                // Cache this promise on global object since it seems to be the only object
+                // in scope across calls.
+                window.promiseSecond = vrDisplay.requestPresent([{ source: canvas }]);
+              }
+              return WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: canvas }], requestAgain);
+            }).then(() => {
+              // First promise succeeded
+              assert_true(vrDisplay.isPresenting, "First promise should successfully fulfill");
+              // Now, validate that the subsequent requestPresent was rejected
+              return promise_rejects(test, null, window.promiseSecond);
+            }).then(() => {
+              delete window.promiseSecond;
+              assert_true(vrDisplay.isPresenting, "Should still be presenting after rejected second promise");
+              return vrDisplay.exitPresent();
+            });
+          }, "WebVR requestPresent fails while another one is in progress");
+
+          promise_test((test) => {
+            return setupVRDisplay(test).then(() => {
+              return WebVRHelpers.RequestPresentOnVRDisplay(vrDisplay, [{ source: canvas }]);
+            }).then(() => {
+              assert_true(vrDisplay.isPresenting, "vrDisplay.isPresenting must be true if requestPresent is fulfilled.");
+              assert_equals(vrDisplay.getLayers().length, 1, "vrDisplay.getLayers() should return one layer.");
+                return vrDisplay.exitPresent();
+            }).then(() => {
+              assert_false(vrDisplay.isPresenting, "vrDisplay.isPresenting must be false if exitPresent is fulfilled.");
+              // exitPresent() should reject since we are no longer presenting.
+              return promise_rejects(test, null, vrDisplay.exitPresent());
+            });
+          }, "WebVR requestPresent fulfilled");
+        }
+
+        runVRTest(startTest);
+    </script>
+</body>
+</html>
diff --git a/dom/vr/test/reftest/VRSimulationDriver.js b/dom/vr/test/reftest/VRSimulationDriver.js
new file mode 100644
index 0000000000..971cdb8626
--- /dev/null
+++ b/dom/vr/test/reftest/VRSimulationDriver.js
@@ -0,0 +1,60 @@
+
+var VRServiceTest;
+var vrMockDisplay;
+
+var VRSimulationDriver = (function() {
+"use strict";
+
+var AttachWebVRDisplay = function() {
+  if (vrMockDisplay) {
+    // Avoid creating multiple displays
+    return Promise.resolve(vrMockDisplay);
+  }
+  var promise = VRServiceTest.attachVRDisplay("VRDisplayTest");
+  promise.then(function (display) {
+    vrMockDisplay = display;
+  });
+
+  return promise;
+};
+
+var SetVRDisplayPose = function(position,
+                                linearVelocity, linearAcceleration,
+                                orientation, angularVelocity,
+                                angularAcceleration) {
+  vrMockDisplay.setPose(position, linearVelocity, linearAcceleration,
+                        orientation, angularVelocity, angularAcceleration);
+};
+
+var SetEyeResolution = function(width, height) {
+  vrMockDisplay.setEyeResolution(width, height);
+}
+
+var SetEyeParameter = function(eye, offsetX, offsetY, offsetZ,
+                               upDegree, rightDegree, downDegree, leftDegree) {
+  vrMockDisplay.setEyeParameter(eye, offsetX, offsetY, offsetZ, upDegree, rightDegree,
+                                downDegree, leftDegree);
+}
+
+var SetMountState = function(isMounted) {
+  vrMockDisplay.setMountState(isMounted);
+}
+
+var UpdateVRDisplay = function() {
+  vrMockDisplay.update();
+}
+
+var API = {
+  AttachWebVRDisplay: AttachWebVRDisplay,
+  SetVRDisplayPose: SetVRDisplayPose,
+  SetEyeResolution: SetEyeResolution,
+  SetEyeParameter: SetEyeParameter,
+  SetMountState: SetMountState,
+  UpdateVRDisplay: UpdateVRDisplay,
+
+  none: false
+};
+
+return API;
+
+}());
\ No newline at end of file
diff --git a/dom/vr/test/reftest/change_size.html b/dom/vr/test/reftest/change_size.html
new file mode 100644
index 0000000000..f810f30821
--- /dev/null
+++ b/dom/vr/test/reftest/change_size.html
@@ -0,0 +1,168 @@
+<!DOCTYPE html>
+<meta charset='UTF-8'>
+<!-- Viewport size change in WebGL and submit it to the VR device as a base64 image.
+If this fails, something is seriously wrong. -->
+<html class="reftest-wait">
+<head>
+  <script type='text/javascript' src='webgl-util.js'></script>
+  <script type='text/javascript' src="VRSimulationDriver.js"></script>
+  <script id="vs" type="x-shader/x-vertex">
+    attribute vec2 aVertCoord;
+
+    void main(void) {
+      gl_Position = vec4(aVertCoord, 0.0, 1.0);
+    }
+  </script>
+  <script id="fs" type="x-shader/x-fragment">
+    precision mediump float;
+
+    void main(void) {
+      gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+    }
+  </script>
+  <script type='text/javascript'>
+    'use strict';
+
+    var submitResult = null;
+    var vrDisplay = null;
+    var webglCanvas = null;
+    var gl = null;
+    var prog = null;
+    var img = null;
+    // The resolution is 540 : 300 (the ratio of 2160 * 1200, like Vive and Oculus)
+    const eyeWidth = 270;
+    const eyeHeight = 300;
+
+    function setStatus(text) {
+      var elem = document.getElementById('status');
+      elem.innerHTML = text;
+    }
+
+    function initVRMock() {
+      VRServiceTest = navigator.requestVRServiceTest();
+      if (!VRServiceTest) {
+        setStatus('VRServiceTest get failed.');
+        return;
+      }
+
+      VRSimulationDriver.AttachWebVRDisplay().then(() => {
+        VRSimulationDriver.SetEyeResolution(eyeWidth, eyeHeight);
+        VRSimulationDriver.UpdateVRDisplay();
+      }).then(() => {
+        // Looking for VR displays
+        if (navigator.getVRDisplays) {
+          submitResult = new VRSubmitFrameResult();
+          navigator.getVRDisplays().then(function (displays) {
+            if (displays.length > 0) {
+              window.addEventListener('vrdisplaypresentchange', onVRPresentChange, false);
+
+              vrDisplay = displays[0];
+              vrDisplay.requestPresent([{ source: webglCanvas }]);
+              vrDisplay.requestAnimationFrame(onAnimationFrame);
+            }
+          });
+        }
+      });
+    }
+
+    function onVRPresentChange() {
+      if (vrDisplay && vrDisplay.isPresenting) {
+        const leftEye = vrDisplay.getEyeParameters("left");
+        const rightEye = vrDisplay.getEyeParameters("right");
+
+        if (leftEye.renderWidth != rightEye.renderWidth ||
+            leftEye.renderWidth != eyeWidth) {
+          setStatus('renderWidth is not equal to eyeWidth.');
+        }
+
+        if (leftEye.renderHeight != rightEye.renderHeight ||
+            leftEye.renderHeight != eyeHeight) {
+          setStatus('renderHeight is not equal to eyeHeight.');
+        }
+        webglCanvas.width = leftEye.renderWidth * 2;
+        webglCanvas.height = leftEye.renderHeight;
+      }
+    }
+
+    function onAnimationFrame() {
+      if (!vrDisplay.isPresenting) {
+        return;
+      }
+
+      gl.clearColor(0.0, 1.0, 0.0, 1.0);
+      gl.clear(gl.COLOR_BUFFER_BIT);
+
+      // Presenting render a stereo view.
+      gl.viewport(0, 0, webglCanvas.width * 0.5, webglCanvas.height);
+      gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
+
+      gl.viewport(webglCanvas.width * 0.5, 0, webglCanvas.width * 0.5, webglCanvas.height);
+      gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
+
+      // Indicate VRDisplay we're done rendering.
+      vrDisplay.submitFrame();
+      if (vrDisplay.getSubmitFrameResult(submitResult)) {
+        if (!img) {
+          img = document.createElement("img");
+          img.onload = function(){
+            // img width will not be eyeWidth * 2 (540), it would
+            // be 544. It is because D3D11 CopyResource changes
+            // the destination image size.
+            if ((img.height == eyeHeight)) {
+              webglCanvas.style.display = 'none';
+              vrDisplay.exitPresent();
+              setTimeout(testComplete, 0);
+            }
+          };
+          img.src = submitResult.base64Image;
+          document.body.appendChild(img);
+        } else {
+          img.src = submitResult.base64Image;
+        }
+      }
+      vrDisplay.requestAnimationFrame(onAnimationFrame);
+    }
+
+    function runTest() {
+      webglCanvas = document.getElementById('canvas');
+      gl = WebGLUtil.getWebGL('canvas');
+      if (!gl) {
+        setStatus('WebGL context creation failed.');
+        return;
+      }
+      gl.disable(gl.DEPTH_TEST);
+      prog = WebGLUtil.createProgramByIds(gl, 'vs', 'fs');
+      if (!prog) {
+        setStatus('Program linking failed.');
+        return;
+      }
+      prog.aVertCoord = gl.getAttribLocation(prog, "aVertCoord");
+
+      var vertCoordArr = new Float32Array([
+        -0.5, -0.5,
+        0.5, -0.5,
+        -0.5, 0.5,
+        0.5, 0.5,
+      ]);
+      var vertCoordBuff = gl.createBuffer();
+      gl.bindBuffer(gl.ARRAY_BUFFER, vertCoordBuff);
+      gl.bufferData(gl.ARRAY_BUFFER, vertCoordArr, gl.STATIC_DRAW);
+      gl.useProgram(prog);
+      gl.enableVertexAttribArray(prog.aVertCoord);
+      gl.vertexAttribPointer(prog.aVertCoord, 2, gl.FLOAT, false, 0, 0);
+
+      initVRMock();
+    }
+
+    function testComplete() {
+      document.documentElement.removeAttribute("class");
+    }
+  </script>
+</head>
+
+<body onload='runTest();'>
+  <canvas id='canvas' width='128' height='128'></canvas>
+  <div id='status'></div>
+</body>
+
+</html>
diff --git a/dom/vr/test/reftest/change_size.png b/dom/vr/test/reftest/change_size.png
new file mode 100644
index 0000000000..fe03114b20
--- /dev/null
+++ b/dom/vr/test/reftest/change_size.png
diff --git a/dom/vr/test/reftest/draw_rect.html b/dom/vr/test/reftest/draw_rect.html
new file mode 100644
index 0000000000..c6f52736c0
--- /dev/null
+++ b/dom/vr/test/reftest/draw_rect.html
@@ -0,0 +1,136 @@
+<!DOCTYPE html>
+<meta charset='UTF-8'>
+<!-- Draw rect in WebGL and submit it to the VR device as a base64 image.
+If this fails, something is seriously wrong. -->
+<html class="reftest-wait">
+<head>
+  <script type='text/javascript' src='webgl-util.js'></script>
+  <script type='text/javascript' src="VRSimulationDriver.js"></script>
+  <script id="vs" type="x-shader/x-vertex">
+    attribute vec2 aVertCoord;
+
+    void main(void) {
+      gl_Position = vec4(aVertCoord, 0.0, 1.0);
+    }
+  </script>
+  <script id="fs" type="x-shader/x-fragment">
+    precision mediump float;
+
+    void main(void) {
+      gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+    }
+  </script>
+  <script type='text/javascript'>
+    'use strict';
+
+    var submitResult = null;
+    var vrDisplay = null;
+    var webglCanvas = null;
+    var gl = null;
+    var prog = null;
+    var img = null;
+
+    function setStatus(text) {
+      var elem = document.getElementById('status');
+      elem.innerHTML = text;
+    }
+
+    function initVRMock() {
+      VRServiceTest = navigator.requestVRServiceTest();
+      if (!VRServiceTest) {
+        setStatus('VRServiceTest get failed.');
+        return;
+      }
+
+      VRSimulationDriver.AttachWebVRDisplay().then(() => {
+        // Looking for VR displays
+        if (navigator.getVRDisplays) {
+          submitResult = new VRSubmitFrameResult();
+          navigator.getVRDisplays().then(function (displays) {
+            if (displays.length > 0) {
+              vrDisplay = displays[0];
+              vrDisplay.requestPresent([{ source: webglCanvas }]);
+              vrDisplay.requestAnimationFrame(onAnimationFrame);
+            }
+          });
+        }
+      });
+    }
+
+    function onAnimationFrame() {
+      if (!vrDisplay.isPresenting) {
+        return;
+      }
+
+      gl.clearColor(0.0, 1.0, 0.0, 1.0);
+      gl.clear(gl.COLOR_BUFFER_BIT);
+
+      // Presenting render a stereo view.
+      gl.viewport(0, 0, webglCanvas.width * 0.5, webglCanvas.height);
+      gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
+
+      gl.viewport(webglCanvas.width * 0.5, 0, webglCanvas.width * 0.5, webglCanvas.height);
+      gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
+
+      // Indicate VRDisplay we're done rendering.
+      vrDisplay.submitFrame();
+      if (vrDisplay.getSubmitFrameResult(submitResult)) {
+        if (!img) {
+          img = document.createElement("img");
+          img.onload = function(){
+            webglCanvas.style.display = 'none';
+            vrDisplay.exitPresent();
+            setTimeout(testComplete, 0);
+          };
+          img.src = submitResult.base64Image;
+          document.body.appendChild(img);
+        } else {
+          img.src = submitResult.base64Image;
+        }
+      }
+      vrDisplay.requestAnimationFrame(onAnimationFrame);
+    }
+
+    function runTest() {
+      webglCanvas = document.getElementById('canvas');
+      gl = WebGLUtil.getWebGL('canvas');
+      if (!gl) {
+        setStatus('WebGL context creation failed.');
+        return;
+      }
+      gl.disable(gl.DEPTH_TEST);
+      prog = WebGLUtil.createProgramByIds(gl, 'vs', 'fs');
+      if (!prog) {
+        setStatus('Program linking failed.');
+        return;
+      }
+      prog.aVertCoord = gl.getAttribLocation(prog, "aVertCoord");
+
+      var vertCoordArr = new Float32Array([
+        -0.5, -0.5,
+        0.5, -0.5,
+        -0.5, 0.5,
+        0.5, 0.5,
+      ]);
+      var vertCoordBuff = gl.createBuffer();
+      gl.bindBuffer(gl.ARRAY_BUFFER, vertCoordBuff);
+      gl.bufferData(gl.ARRAY_BUFFER, vertCoordArr, gl.STATIC_DRAW);
+      gl.useProgram(prog);
+      gl.enableVertexAttribArray(prog.aVertCoord);
+      gl.vertexAttribPointer(prog.aVertCoord, 2, gl.FLOAT, false, 0, 0);
+
+      initVRMock();
+    }
+
+    function testComplete() {
+      document.documentElement.removeAttribute("class");
+    }
+  </script>
+</head>
+
+<body onload='runTest();'>
+  <canvas id='canvas' width='256' height='256'></canvas>
+  <div id='status'></div>
+</body>
+
+</html>
diff --git a/dom/vr/test/reftest/draw_rect.png b/dom/vr/test/reftest/draw_rect.png
new file mode 100644
index 0000000000..0f4d24a0d1
--- /dev/null
+++ b/dom/vr/test/reftest/draw_rect.png
diff --git a/dom/vr/test/reftest/reftest.list b/dom/vr/test/reftest/reftest.list
new file mode 100644
index 0000000000..53ecc53c63
--- /dev/null
+++ b/dom/vr/test/reftest/reftest.list
@@ -0,0 +1,10 @@
+# WebVR Reftests
+# Please confirm there is no other VR display connected. Otherwise, VRPuppetDisplay can't be attached.
+defaults pref(dom.vr.puppet.enabled,true) pref(dom.vr.test.enabled,true) pref(dom.vr.require-gesture,false) pref(dom.vr.puppet.submitframe,1) pref(dom.vr.display.rafMaxDuration,200) pref(dom.vr.display.enumerate.interval,0) pref(dom.vr.controller.enumerate.interval,0)
+# WebVR Tests have been disabled as refactoring of gfxVRPuppet is landing.  Dependencies for re-enabling these are tracked by meta bug 1555185.
+# VR SubmitFrame is only implemented for D3D11.1 and MacOSX now.
+# Our Windows 7 test machines don't support D3D11.1, so we run these tests on Windows 8+ only.
+# skip-if((!winWidget&&release_or_beta)||Android||gtkWidget||!layersGPUAccelerated||/^Windows\x20NT\x206\.1/.test(http.oscpu)) == draw_rect.html wrapper.html?draw_rect.png
+# On MacOSX platform, getting different color interpolation result.
+# For lower resolution Mac hardware, we need to adjust it to fuzzy-if(cocoaWidget,0-1,0-1200).
+# fuzzy-if(/^Windows\x20NT\x2010\.0/.test(http.oscpu)||cocoaWidget,0-1,0-600) skip-if((!winWidget&&release_or_beta)||Android||gtkWidget||!layersGPUAccelerated||/^Windows\x20NT\x206\.1/.test(http.oscpu)) == change_size.html wrapper.html?change_size.png
diff --git a/dom/vr/test/reftest/webgl-util.js b/dom/vr/test/reftest/webgl-util.js
new file mode 100644
index 0000000000..21ef9cf0ff
--- /dev/null
+++ b/dom/vr/test/reftest/webgl-util.js
@@ -0,0 +1,170 @@
+WebGLUtil = (function() {
+  // ---------------------------------------------------------------------------
+  // Error handling (for obvious failures, such as invalid element ids)
+
+  function defaultErrorFunc(str) {
+    console.log('Error: ' + str);
+  }
+
+  var gErrorFunc = defaultErrorFunc;
+  function setErrorFunc(func) {
+    gErrorFunc = func;
+  }
+
+  function error(str) {
+    gErrorFunc(str);
+  }
+
+  // ---------------------------------------------------------------------------
+  // Warning handling (for failures that may be intentional)
+
+  function defaultWarningFunc(str) {
+    console.log('Warning: ' + str);
+  }
+
+  var gWarningFunc = defaultWarningFunc;
+  function setWarningFunc(func) {
+    gWarningFunc = func;
+  }
+
+  function warning(str) {
+    gWarningFunc(str);
+  }
+
+  // ---------------------------------------------------------------------------
+  // WebGL helpers
+
+  function getWebGL(canvasId, requireConformant, attributes) {
+    // `requireConformant` will default to falsey if it is not supplied.
+
+    var canvas = document.getElementById(canvasId);
+
+    var gl = null;
+    try {
+      gl = canvas.getContext('webgl', attributes);
+    } catch(e) {}
+
+    if (!gl && !requireConformant) {
+      try {
+        gl = canvas.getContext('experimental-webgl', attributes);
+      } catch(e) {}
+    }
+
+    if (!gl) {
+      error('WebGL context could not be retrieved from \'' + canvasId + '\'.');
+      return null;
+    }
+
+    return gl;
+  }
+
+  function withWebGL2(canvasId, callback, onFinished) {
+    var run = function() {
+      var canvas = document.getElementById(canvasId);
+
+      var gl = null;
+      try {
+        gl = canvas.getContext('webgl2');
+      } catch(e) {}
+
+      if (!gl) {
+        todo(false, 'WebGL2 is not supported');
+        onFinished();
+        return;
+      }
+
+      function errorFunc(str) {
+        ok(false, 'Error: ' + str);
+      }
+      setErrorFunc(errorFunc);
+      setWarningFunc(errorFunc);
+
+      callback(gl);
+      onFinished();
+    };
+
+    try {
+      var prefArrArr = [
+        ['webgl.force-enabled', true],
+        ['webgl.enable-webgl2', true],
+      ];
+      var prefEnv = {'set': prefArrArr};
+      SpecialPowers.pushPrefEnv(prefEnv, run);
+    } catch (e) {
+      warning('No SpecialPowers, but trying WebGL2 anyway...');
+      run();
+    }
+  }
+
+  function getContentFromElem(elem) {
+    var str = "";
+    var k = elem.firstChild;
+    while (k) {
+      if (k.nodeType == 3)
+        str += k.textContent;
+
+      k = k.nextSibling;
+    }
+
+    return str;
+  }
+
+  // Returns a valid shader, or null on errors.
+  function createShaderById(gl, id) {
+    var elem = document.getElementById(id);
+    if (!elem) {
+      error('Failed to create shader from non-existent id \'' + id + '\'.');
+      return null;
+    }
+
+    var src = getContentFromElem(elem);
+
+    var shader;
+    if (elem.type == "x-shader/x-fragment") {
+      shader = gl.createShader(gl.FRAGMENT_SHADER);
+    } else if (elem.type == "x-shader/x-vertex") {
+      shader = gl.createShader(gl.VERTEX_SHADER);
+    } else {
+      error('Bad MIME type for shader \'' + id + '\': ' + elem.type + '.');
+      return null;
+    }
+
+    gl.shaderSource(shader, src);
+    gl.compileShader(shader);
+
+    return shader;
+  }
+
+  function createProgramByIds(gl, vsId, fsId) {
+    var vs = createShaderById(gl, vsId);
+    var fs = createShaderById(gl, fsId);
+    if (!vs || !fs)
+      return null;
+
+    var prog = gl.createProgram();
+    gl.attachShader(prog, vs);
+    gl.attachShader(prog, fs);
+    gl.linkProgram(prog);
+
+    if (!gl.getProgramParameter(prog, gl.LINK_STATUS)) {
+      var str = "Shader program linking failed:";
+      str += "\nShader program info log:\n" + gl.getProgramInfoLog(prog);
+      str += "\n\nVert shader log:\n" + gl.getShaderInfoLog(vs);
+      str += "\n\nFrag shader log:\n" + gl.getShaderInfoLog(fs);
+      warning(str);
+      return null;
+    }
+
+    return prog;
+  }
+
+  return {
+    setErrorFunc: setErrorFunc,
+    setWarningFunc: setWarningFunc,
+
+    getWebGL: getWebGL,
+    withWebGL2: withWebGL2,
+    createShaderById: createShaderById,
+    createProgramByIds: createProgramByIds,
+  };
+})();
diff --git a/dom/vr/test/reftest/wrapper.html b/dom/vr/test/reftest/wrapper.html
new file mode 100644
index 0000000000..40d0de6e42
--- /dev/null
+++ b/dom/vr/test/reftest/wrapper.html
@@ -0,0 +1,26 @@
+<!DOCTYPE HTML>
+<html class="reftest-wait">
+<head>
+<title>Image reftest wrapper</title>
+<style type="text/css">
+  #image1 { background-color: rgb(10, 100, 250); }
+</style>
+<script>
+  // The image is loaded async after the page loads
+  // wait for it to finish loading
+  function onImageLoad() {
+    document.documentElement.removeAttribute("class");
+  };
+</script>
+</head>
+<body>
+<img id="image1">
+<script>
+  // Use as "wrapper.html?image.png"
+  var imgURL = document.location.search.substr(1);
+  document.images[0].onload = onImageLoad;
+  document.images[0].onerror = onImageLoad;
+  document.images[0].src = imgURL;
+</script>
+</body>
+</html>