--- a/dom/media/MediaFormatReader.cpp
+++ b/dom/media/MediaFormatReader.cpp
@@ -409,18 +409,22 @@ MediaFormatReader::EnsureDecodersSetup()
       // JavaScript player app. Note: we still go through the motions here
       // even if EME is disabled, so that if script tries and fails to create
       // a CDM, we can detect that and notify chrome and show some UI
       // explaining that we failed due to EME being disabled.
       nsRefPtr<CDMProxy> proxy;
       {
         ReentrantMonitorAutoEnter mon(mDecoder->GetReentrantMonitor());
         proxy = mDecoder->GetCDMProxy();
+        MOZ_ASSERT(proxy);
+
+        CDMCaps::AutoLock caps(proxy->Capabilites());
+        mInfo.mVideo.mIsRenderedExternally = caps.CanRenderVideo();
+        mInfo.mAudio.mIsRenderedExternally = caps.CanRenderAudio();
       }
-      MOZ_ASSERT(proxy);
 
       mPlatform = PlatformDecoderModule::CreateCDMWrapper(proxy);
       NS_ENSURE_TRUE(mPlatform, false);
 #else
       // EME not supported.
       return false;
 #endif
     } else {

--- a/dom/media/MediaInfo.h
+++ b/dom/media/MediaInfo.h
@@ -41,16 +41,17 @@ public:
     : mId(aId)
     , mKind(aKind)
     , mLabel(aLabel)
     , mLanguage(aLanguage)
     , mEnabled(aEnabled)
     , mTrackId(aTrackId)
     , mDuration(0)
     , mMediaTime(0)
+    , mIsRenderedExternally(false)
     , mType(aType)
   {
     MOZ_COUNT_CTOR(TrackInfo);
   }
 
   // Only used for backward compatibility. Do not use in new code.
   void Init(TrackType aType,
             const nsAString& aId,
@@ -78,16 +79,20 @@ public:
 
   TrackID mTrackId;
 
   nsAutoCString mMimeType;
   int64_t mDuration;
   int64_t mMediaTime;
   CryptoTrack mCrypto;
 
+  // True if the track is gonna be (decrypted)/decoded and
+  // rendered directly by non-gecko components.
+  bool mIsRenderedExternally;
+
   virtual AudioInfo* GetAsAudioInfo()
   {
     return nullptr;
   }
   virtual VideoInfo* GetAsVideoInfo()
   {
     return nullptr;
   }
@@ -142,16 +147,17 @@ protected:
     mLabel = aOther.mLabel;
     mLanguage = aOther.mLanguage;
     mEnabled = aOther.mEnabled;
     mTrackId = aOther.mTrackId;
     mMimeType = aOther.mMimeType;
     mDuration = aOther.mDuration;
     mMediaTime = aOther.mMediaTime;
     mCrypto = aOther.mCrypto;
+    mIsRenderedExternally = aOther.mIsRenderedExternally;
     mType = aOther.mType;
     MOZ_COUNT_CTOR(TrackInfo);
   }
 
 private:
   TrackType mType;
 };