diff --git a/app/src/main/cpp/Device.h b/app/src/main/cpp/Device.h
index 68713b4113..62d9dccf94 100644
--- a/app/src/main/cpp/Device.h
+++ b/app/src/main/cpp/Device.h
@@ -16,6 +16,7 @@ const CapabilityFlags AngularAcceleration = 1 << 5;
 const CapabilityFlags LinearAcceleration = 1 << 6;
 const CapabilityFlags StageParameters = 1 << 7;
 const CapabilityFlags MountDetection = 1 << 8;
+const CapabilityFlags PositionNeckModel = 1 << 9;
 enum class Eye { Left, Right };
 enum class RenderMode { StandAlone, Immersive };
 const int32_t EyeCount = 2;
diff --git a/app/src/main/cpp/DeviceDelegate.h b/app/src/main/cpp/DeviceDelegate.h
index ff99625e60..d8b98d0f88 100644
--- a/app/src/main/cpp/DeviceDelegate.h
+++ b/app/src/main/cpp/DeviceDelegate.h
@@ -39,6 +39,7 @@ class ImmersiveDisplay {
                               const double aBottomDegrees) = 0;
   virtual void SetEyeOffset(const device::Eye aEye, const float aX, const float aY, const float aZ) = 0;
   virtual void SetEyeResolution(const int32_t aWidth, const int32_t aHeight) = 0;
+  virtual void SetSittingToStandingTransform(const vrb::Matrix& aTransform) = 0;
   virtual void CompleteEnumeration() = 0;
 };
 
diff --git a/app/src/main/cpp/ExternalVR.cpp b/app/src/main/cpp/ExternalVR.cpp
index a881e771c2..3a3d61bb1a 100644
--- a/app/src/main/cpp/ExternalVR.cpp
+++ b/app/src/main/cpp/ExternalVR.cpp
@@ -256,6 +256,9 @@ ExternalVR::SetCapabilityFlags(const device::CapabilityFlags aFlags) {
   if (device::MountDetection & aFlags) {
     result |= static_cast<uint16_t>(mozilla::gfx::VRDisplayCapabilityFlags::Cap_MountDetection);
   }
+  if (device::PositionNeckModel & aFlags) {
+    result |= static_cast<uint16_t>(mozilla::gfx::VRDisplayCapabilityFlags::Cap_PositionNeckModel);
+  }
   m.deviceCapabilities = aFlags;
   m.system.displayState.capabilityFlags = static_cast<mozilla::gfx::VRDisplayCapabilityFlags>(result);
   m.system.sensorState.flags = m.system.displayState.capabilityFlags;
@@ -292,6 +295,11 @@ ExternalVR::SetEyeResolution(const int32_t aWidth, const int32_t aHeight) {
   m.system.displayState.eyeResolution.height = aHeight;
 }
 
+void
+ExternalVR::SetSittingToStandingTransform(const vrb::Matrix& aTransform) {
+  memcpy(&(m.system.displayState.sittingToStandingTransform), aTransform.Data(), sizeof(m.system.displayState.sittingToStandingTransform));
+}
+
 void
 ExternalVR::PushSystemState() {
   Lock lock(m.data.systemMutex);
diff --git a/app/src/main/cpp/ExternalVR.h b/app/src/main/cpp/ExternalVR.h
index 5011c3d97f..00dc7f0c2d 100644
--- a/app/src/main/cpp/ExternalVR.h
+++ b/app/src/main/cpp/ExternalVR.h
@@ -44,6 +44,7 @@ class ExternalVR : public ImmersiveDisplay {
                       const double aBottomDegrees) override;
   void SetEyeOffset(const device::Eye aEye, const float aX, const float aY, const float aZ) override;
   void SetEyeResolution(const int32_t aX, const int32_t aY) override;
+  void SetSittingToStandingTransform(const vrb::Matrix& aTransform) override;
   void CompleteEnumeration() override;
   // ExternalVR interface
   void PushSystemState();
diff --git a/app/src/main/cpp/moz_external_vr.h b/app/src/main/cpp/moz_external_vr.h
index ecd4bea64a..7d4f1f9671 100644
--- a/app/src/main/cpp/moz_external_vr.h
+++ b/app/src/main/cpp/moz_external_vr.h
@@ -34,7 +34,7 @@ enum class GamepadCapabilityFlags : uint16_t;
 #endif  //  MOZILLA_INTERNAL_API
 namespace gfx {
 
-static const int32_t kVRExternalVersion = 6;
+static const int32_t kVRExternalVersion = 7;
 
 // We assign VR presentations to groups with a bitmask.
 // Currently, we will only display either content or chrome.
@@ -88,26 +88,26 @@ enum class ControllerCapabilityFlags : uint16_t {
   /**
    * Cap_Position is set if the Gamepad is capable of tracking its position.
    */
-  Cap_Position = 1 << 1,
+      Cap_Position = 1 << 1,
   /**
    * Cap_Orientation is set if the Gamepad is capable of tracking its
    * orientation.
    */
-  Cap_Orientation = 1 << 2,
+      Cap_Orientation = 1 << 2,
   /**
    * Cap_AngularAcceleration is set if the Gamepad is capable of tracking its
    * angular acceleration.
    */
-  Cap_AngularAcceleration = 1 << 3,
+      Cap_AngularAcceleration = 1 << 3,
   /**
    * Cap_LinearAcceleration is set if the Gamepad is capable of tracking its
    * linear acceleration.
    */
-  Cap_LinearAcceleration = 1 << 4,
+      Cap_LinearAcceleration = 1 << 4,
   /**
    * Cap_All used for validity checking during IPC serialization
    */
-  Cap_All = (1 << 5) - 1
+      Cap_All = (1 << 5) - 1
 };
 
 #endif  // ifndef MOZILLA_INTERNAL_API
@@ -117,12 +117,12 @@ enum class VRDisplayCapabilityFlags : uint16_t {
   /**
    * Cap_Position is set if the VRDisplay is capable of tracking its position.
    */
-  Cap_Position = 1 << 1,
+      Cap_Position = 1 << 1,
   /**
    * Cap_Orientation is set if the VRDisplay is capable of tracking its
    * orientation.
    */
-  Cap_Orientation = 1 << 2,
+      Cap_Orientation = 1 << 2,
   /**
    * Cap_Present is set if the VRDisplay is capable of presenting content to an
    * HMD or similar device.  Can be used to indicate "magic window" devices that
@@ -130,7 +130,7 @@ enum class VRDisplayCapabilityFlags : uint16_t {
    * meaningful. If false then calls to requestPresent should always fail, and
    * getEyeParameters should return null.
    */
-  Cap_Present = 1 << 3,
+      Cap_Present = 1 << 3,
   /**
    * Cap_External is set if the VRDisplay is separate from the device's
    * primary display. If presenting VR content will obscure
@@ -138,31 +138,36 @@ enum class VRDisplayCapabilityFlags : uint16_t {
    * un-set, the application should not attempt to mirror VR content
    * or update non-VR UI because that content will not be visible.
    */
-  Cap_External = 1 << 4,
+      Cap_External = 1 << 4,
   /**
    * Cap_AngularAcceleration is set if the VRDisplay is capable of tracking its
    * angular acceleration.
    */
-  Cap_AngularAcceleration = 1 << 5,
+      Cap_AngularAcceleration = 1 << 5,
   /**
    * Cap_LinearAcceleration is set if the VRDisplay is capable of tracking its
    * linear acceleration.
    */
-  Cap_LinearAcceleration = 1 << 6,
+      Cap_LinearAcceleration = 1 << 6,
   /**
    * Cap_StageParameters is set if the VRDisplay is capable of room scale VR
    * and can report the StageParameters to describe the space.
    */
-  Cap_StageParameters = 1 << 7,
+      Cap_StageParameters = 1 << 7,
   /**
    * Cap_MountDetection is set if the VRDisplay is capable of sensing when the
    * user is wearing the device.
    */
-  Cap_MountDetection = 1 << 8,
+      Cap_MountDetection = 1 << 8,
+  /**
+   * Cap_PositionNeckModel is set if the VRDisplay is capable of setting a
+   * neck model in position even if still doesn't support 6DOF tracking.
+   */
+      Cap_PositionNeckModel = 1 << 9,
   /**
    * Cap_All used for validity checking during IPC serialization
    */
-  Cap_All = (1 << 9) - 1
+      Cap_All = (1 << 9) - 1
 };
 
 #ifdef MOZILLA_INTERNAL_API
diff --git a/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp b/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp
index 5d95a363a2..fec88e94d5 100644
--- a/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp
+++ b/app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp
@@ -1116,9 +1116,13 @@ DeviceDelegateOculusVR::StartFrame() {
   if (m.immersiveDisplay) {
     m.immersiveDisplay->SetEyeOffset(device::Eye::Left, -ipd * 0.5f, 0.f, 0.f);
     m.immersiveDisplay->SetEyeOffset(device::Eye::Right, ipd * 0.5f, 0.f, 0.f);
-    device::CapabilityFlags caps = device::Orientation | device::Present;
+    device::CapabilityFlags caps = device::Orientation | device::Present | device::StageParameters;
     if (m.predictedTracking.Status & VRAPI_TRACKING_STATUS_POSITION_TRACKED) {
       caps |= device::Position;
+      m.immersiveDisplay->SetSittingToStandingTransform(vrb::Matrix::Identity());
+    } else {
+      caps |= device::Position;
+      m.immersiveDisplay->SetSittingToStandingTransform(vrb::Matrix::Translation(vrb::Vector(0.0f, 1.65f, 0.0f)));
     }
     m.immersiveDisplay->SetCapabilityFlags(caps);
   }