--- a/dom/media/webrtc/MediaEngineWebRTC.cpp
+++ b/dom/media/webrtc/MediaEngineWebRTC.cpp
@@ -300,36 +300,31 @@ MediaEngineWebRTC::EnumerateMicrophoneDe
   }
 }
 
 void
 MediaEngineWebRTC::EnumerateDevices(uint64_t aWindowId,
                                     dom::MediaSourceEnum aMediaSource,
                                     nsTArray<RefPtr<MediaEngineSource> >* aSources)
 {
-  // We spawn threads to handle gUM runnables, so we must protect the member vars
+  // We spawn threads to handle gUM runnables, so we must protect the member
+  // vars
   MutexAutoLock lock(mMutex);
   if (MediaEngineSource::IsVideo(aMediaSource)) {
     EnumerateVideoDevices(aWindowId, aMediaSource, aSources);
   } else if (aMediaSource == dom::MediaSourceEnum::AudioCapture) {
     RefPtr<MediaEngineWebRTCAudioCaptureSource> audioCaptureSource =
       new MediaEngineWebRTCAudioCaptureSource(nullptr);
     aSources->AppendElement(audioCaptureSource);
   } else {
     MOZ_ASSERT(aMediaSource == dom::MediaSourceEnum::Microphone);
     EnumerateMicrophoneDevices(aWindowId, aSources);
   }
 }
 
-bool
-MediaEngineWebRTC::SupportsDuplex()
-{
-  return mFullDuplex;
-}
-
 void
 MediaEngineWebRTC::ReleaseResourcesForWindow(uint64_t aWindowId)
 {
   {
     nsRefPtrHashtable<nsStringHashKey, MediaEngineSource>*
       audioDevicesForThisWindow = mAudioSources.Get(aWindowId);
 
     if (audioDevicesForThisWindow) {

--- a/dom/media/webrtc/MediaEngineWebRTC.h
+++ b/dom/media/webrtc/MediaEngineWebRTC.h
@@ -438,37 +438,30 @@ public:
   explicit MediaEngineWebRTC(MediaEnginePrefs& aPrefs);
 
   virtual void SetFakeDeviceChangeEvents() override;
 
   // Clients should ensure to clean-up sources video/audio sources
   // before invoking Shutdown on this class.
   void Shutdown() override;
 
-  // Returns whether the host supports duplex audio stream.
-  bool SupportsDuplex();
-
   void EnumerateDevices(uint64_t aWindowId,
                         dom::MediaSourceEnum,
                         nsTArray<RefPtr<MediaEngineSource>>*) override;
   void ReleaseResourcesForWindow(uint64_t aWindowId) override;
 private:
-  ~MediaEngineWebRTC() = default;
   void EnumerateVideoDevices(uint64_t aWindowId,
                              dom::MediaSourceEnum,
                              nsTArray<RefPtr<MediaEngineSource>>*);
   void EnumerateMicrophoneDevices(uint64_t aWindowId,
                                   nsTArray<RefPtr<MediaEngineSource>>*);
 
-  nsCOMPtr<nsIThread> mThread;
-
   // gUM runnables can e.g. Enumerate from multiple threads
   Mutex mMutex;
   RefPtr<mozilla::CubebDeviceEnumerator> mEnumerator;
-  bool mFullDuplex;
   bool mDelayAgnostic;
   bool mExtendedFilter;
   bool mHasTabVideoSource;
 
   // Maps WindowID to a map of device uuid to their MediaEngineSource,
   // separately for audio and video.
   nsClassHashtable<nsUint64HashKey,
                     nsRefPtrHashtable<nsStringHashKey,