diff --git a/dom/media/DecoderTraits.cpp b/dom/media/DecoderTraits.cpp
index c645889742b..0d46a19eefe 100644
--- a/dom/media/DecoderTraits.cpp
+++ b/dom/media/DecoderTraits.cpp
@@ -23,6 +23,7 @@
 #ifdef MOZ_WEBM
 #include "WebMDecoder.h"
 #include "WebMReader.h"
+#include "WebMDemuxer.h"
 #endif
 #ifdef MOZ_RAW
 #include "RawDecoder.h"
@@ -698,7 +699,9 @@ MediaDecoderReader* DecoderTraits::CreateReader(const nsACString& aType, Abstrac
 #endif
 #ifdef MOZ_WEBM
   if (IsWebMType(aType)) {
-    decoderReader = new WebMReader(aDecoder);
+    decoderReader = Preferences::GetBool("media.format-reader.webm", true) ?
+      static_cast<MediaDecoderReader*>(new MediaFormatReader(aDecoder, new WebMDemuxer(aDecoder->GetResource()))) :
+      new WebMReader(aDecoder);
   } else
 #endif
 #ifdef MOZ_DIRECTSHOW
diff --git a/dom/media/MediaFormatReader.cpp b/dom/media/MediaFormatReader.cpp
index 1ff2bc8949b..bd53a11325d 100644
--- a/dom/media/MediaFormatReader.cpp
+++ b/dom/media/MediaFormatReader.cpp
@@ -258,13 +258,15 @@ bool MediaFormatReader::IsWaitingOnCDMResource() {
 bool
 MediaFormatReader::IsSupportedAudioMimeType(const nsACString& aMimeType)
 {
-  return mPlatform && mPlatform->SupportsMimeType(aMimeType);
+  return mPlatform && (mPlatform->SupportsMimeType(aMimeType) ||
+    PlatformDecoderModule::AgnosticMimeType(aMimeType));
 }
 
 bool
 MediaFormatReader::IsSupportedVideoMimeType(const nsACString& aMimeType)
 {
-  return mPlatform && mPlatform->SupportsMimeType(aMimeType);
+  return mPlatform && (mPlatform->SupportsMimeType(aMimeType) ||
+    PlatformDecoderModule::AgnosticMimeType(aMimeType));
 }
 
 nsRefPtr<MediaDecoderReader::MetadataPromise>
diff --git a/dom/media/mediasource/MediaSourceReader.cpp b/dom/media/mediasource/MediaSourceReader.cpp
index e11a01ff489..fae257e2783 100644
--- a/dom/media/mediasource/MediaSourceReader.cpp
+++ b/dom/media/mediasource/MediaSourceReader.cpp
@@ -25,6 +25,7 @@
 
 #ifdef MOZ_WEBM
 #include "WebMReader.h"
+#include "WebMDemuxer.h"
 #endif
 
 extern PRLogModuleInfo* GetMediaSourceLog();
@@ -718,7 +719,12 @@ CreateReaderForType(const nsACString& aType, AbstractMediaDecoder* aDecoder,
 
 #ifdef MOZ_WEBM
   if (DecoderTraits::IsWebMType(aType)) {
-    return new WebMReader(aDecoder, aBorrowedTaskQueue);
+    bool useFormatDecoder =
+      Preferences::GetBool("media.mediasource.format-reader.webm", true);
+    MediaDecoderReader* reader = useFormatDecoder ?
+      static_cast<MediaDecoderReader*>(new MediaFormatReader(aDecoder, new WebMDemuxer(aDecoder->GetResource()), aBorrowedTaskQueue)) :
+      new WebMReader(aDecoder, aBorrowedTaskQueue);
+    return reader;
   }
 #endif
 
diff --git a/dom/media/platforms/PlatformDecoderModule.cpp b/dom/media/platforms/PlatformDecoderModule.cpp
index c1e088053a2..14f80d89d1f 100644
--- a/dom/media/platforms/PlatformDecoderModule.cpp
+++ b/dom/media/platforms/PlatformDecoderModule.cpp
@@ -35,8 +35,13 @@
 #include "MediaInfo.h"
 #include "H264Converter.h"
 
+#include "OpusDecoder.h"
+#include "VorbisDecoder.h"
+#include "VPXDecoder.h"
+
 namespace mozilla {
 
+extern already_AddRefed<PlatformDecoderModule> CreateAgnosticDecoderModule();
 extern already_AddRefed<PlatformDecoderModule> CreateBlankDecoderModule();
 
 bool PlatformDecoderModule::sUseBlankDecoder = false;
@@ -124,7 +129,7 @@ PlatformDecoderModule::Create()
   if (m && NS_SUCCEEDED(m->Startup())) {
     return m.forget();
   }
-  return nullptr;
+  return CreateAgnosticDecoderModule();
 }
 
 /* static */
@@ -184,10 +189,22 @@ PlatformDecoderModule::CreateDecoder(const TrackInfo& aConfig,
 {
   nsRefPtr<MediaDataDecoder> m;
 
+  bool hasPlatformDecoder = SupportsMimeType(aConfig.mMimeType);
+
   if (aConfig.GetAsAudioInfo()) {
-    m = CreateAudioDecoder(*aConfig.GetAsAudioInfo(),
-                           aTaskQueue,
-                           aCallback);
+    if (!hasPlatformDecoder && VorbisDataDecoder::IsVorbis(aConfig.mMimeType)) {
+      m = new VorbisDataDecoder(*aConfig.GetAsAudioInfo(),
+                                aTaskQueue,
+                                aCallback);
+    } else if (!hasPlatformDecoder && OpusDataDecoder::IsOpus(aConfig.mMimeType)) {
+      m = new OpusDataDecoder(*aConfig.GetAsAudioInfo(),
+                              aTaskQueue,
+                              aCallback);
+    } else {
+      m = CreateAudioDecoder(*aConfig.GetAsAudioInfo(),
+                             aTaskQueue,
+                             aCallback);
+    }
     return m.forget();
   }
 
@@ -202,6 +219,11 @@ PlatformDecoderModule::CreateDecoder(const TrackInfo& aConfig,
                           aImageContainer,
                           aTaskQueue,
                           aCallback);
+  } else if (!hasPlatformDecoder && VPXDecoder::IsVPX(aConfig.mMimeType)) {
+    m = new VPXDecoder(*aConfig.GetAsVideoInfo(),
+                       aImageContainer,
+                       aTaskQueue,
+                       aCallback);
   } else {
     m = CreateVideoDecoder(*aConfig.GetAsVideoInfo(),
                            aLayersBackend,
@@ -220,4 +242,14 @@ PlatformDecoderModule::SupportsMimeType(const nsACString& aMimeType)
     aMimeType.EqualsLiteral("video/avc");
 }
 
+/* static */
+bool
+PlatformDecoderModule::AgnosticMimeType(const nsACString& aMimeType)
+{
+  return VPXDecoder::IsVPX(aMimeType) ||
+    OpusDataDecoder::IsOpus(aMimeType) ||
+    VorbisDataDecoder::IsVorbis(aMimeType);
+}
+
+
 } // namespace mozilla
diff --git a/dom/media/platforms/PlatformDecoderModule.h b/dom/media/platforms/PlatformDecoderModule.h
index dc1fc7f13f2..113d089c193 100644
--- a/dom/media/platforms/PlatformDecoderModule.h
+++ b/dom/media/platforms/PlatformDecoderModule.h
@@ -93,6 +93,10 @@ public:
   // to be extended
   virtual bool SupportsMimeType(const nsACString& aMimeType);
 
+  // MimeType can be decoded with shipped decoders if no platform decoders exist
+  static bool AgnosticMimeType(const nsACString& aMimeType);
+
+
   enum ConversionRequired {
     kNeedNone,
     kNeedAVCC,
@@ -107,7 +111,7 @@ public:
   virtual void DisableHardwareAcceleration() {}
 
   virtual bool SupportsSharedDecoders(const VideoInfo& aConfig) const {
-    return true;
+    return !AgnosticMimeType(aConfig.mMimeType);
   }
 
 protected:
diff --git a/dom/media/platforms/agnostic/BlankDecoderModule.cpp b/dom/media/platforms/agnostic/BlankDecoderModule.cpp
index 968b4792167..62bfef72f07 100644
--- a/dom/media/platforms/agnostic/BlankDecoderModule.cpp
+++ b/dom/media/platforms/agnostic/BlankDecoderModule.cpp
@@ -246,6 +246,11 @@ public:
     return true;
   }
 
+  virtual bool
+  SupportsSharedDecoders(const VideoInfo& aConfig) const override {
+    return false;
+  }
+
   virtual ConversionRequired
   DecoderNeedsConversion(const TrackInfo& aConfig) const override
   {
@@ -254,10 +259,27 @@ public:
 
 };
 
+class AgnosticDecoderModule : public BlankDecoderModule {
+public:
+
+  bool SupportsMimeType(const nsACString& aMimeType) override
+  {
+    // This module does not support any decoders itself,
+    // agnostic decoders are created in PlatformDecoderModule::CreateDecoder
+    return false;
+  }
+};
+
 already_AddRefed<PlatformDecoderModule> CreateBlankDecoderModule()
 {
   nsRefPtr<PlatformDecoderModule> pdm = new BlankDecoderModule();
   return pdm.forget();
 }
 
+already_AddRefed<PlatformDecoderModule> CreateAgnosticDecoderModule()
+{
+  nsRefPtr<PlatformDecoderModule> adm = new AgnosticDecoderModule();
+  return adm.forget();
+}
+
 } // namespace mozilla
diff --git a/dom/media/platforms/wmf/WMFDecoderModule.cpp b/dom/media/platforms/wmf/WMFDecoderModule.cpp
index 6f814633f89..f070642d2f2 100644
--- a/dom/media/platforms/wmf/WMFDecoderModule.cpp
+++ b/dom/media/platforms/wmf/WMFDecoderModule.cpp
@@ -26,6 +26,7 @@ namespace mozilla {
 static bool sIsWMFEnabled = false;
 static bool sDXVAEnabled = false;
 static int  sNumDecoderThreads = -1;
+static bool sIsIntelDecoderEnabled = false;
 
 WMFDecoderModule::WMFDecoderModule()
   : mWMFInitialized(false)
@@ -44,6 +45,7 @@ void
 WMFDecoderModule::DisableHardwareAcceleration()
 {
   sDXVAEnabled = false;
+  sIsIntelDecoderEnabled = false;
 }
 
 static void
@@ -72,6 +74,7 @@ WMFDecoderModule::Init()
   MOZ_ASSERT(NS_IsMainThread(), "Must be on main thread.");
   sIsWMFEnabled = Preferences::GetBool("media.windows-media-foundation.enabled", false);
   sDXVAEnabled = gfxPlatform::GetPlatform()->CanUseHardwareVideoDecoding();
+  sIsIntelDecoderEnabled = Preferences::GetBool("media.webm.intel_decoder.enabled", false);
   SetNumOfDecoderThreads();
 }
 
@@ -145,7 +148,8 @@ WMFDecoderModule::SupportsSharedDecoders(const VideoInfo& aConfig) const
 {
   // If DXVA is enabled, but we're not going to use it for this specific config, then
   // we can't use the shared decoder.
-  return !sDXVAEnabled || ShouldUseDXVA(aConfig);
+  return !AgnosticMimeType(aConfig.mMimeType) &&
+    (!sDXVAEnabled || ShouldUseDXVA(aConfig));
 }
 
 bool
@@ -153,10 +157,11 @@ WMFDecoderModule::SupportsMimeType(const nsACString& aMimeType)
 {
   return aMimeType.EqualsLiteral("video/mp4") ||
          aMimeType.EqualsLiteral("video/avc") ||
-         aMimeType.EqualsLiteral("video/webm; codecs=vp8") ||
-         aMimeType.EqualsLiteral("video/webm; codecs=vp9") ||
          aMimeType.EqualsLiteral("audio/mp4a-latm") ||
-         aMimeType.EqualsLiteral("audio/mpeg");
+         aMimeType.EqualsLiteral("audio/mpeg") ||
+         (sIsIntelDecoderEnabled &&
+          (aMimeType.EqualsLiteral("video/webm; codecs=vp8") ||
+           aMimeType.EqualsLiteral("video/webm; codecs=vp9")));
 }
 
 PlatformDecoderModule::ConversionRequired
diff --git a/dom/media/webm/WebMDecoder.cpp b/dom/media/webm/WebMDecoder.cpp
index e80380144f7..7a74a3dc0b1 100644
--- a/dom/media/webm/WebMDecoder.cpp
+++ b/dom/media/webm/WebMDecoder.cpp
@@ -4,7 +4,10 @@
  * 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/Preferences.h"
 #include "MediaDecoderStateMachine.h"
+#include "MediaFormatReader.h"
+#include "WebMDemuxer.h"
 #include "WebMReader.h"
 #include "WebMDecoder.h"
 
@@ -12,7 +15,12 @@ namespace mozilla {
 
 MediaDecoderStateMachine* WebMDecoder::CreateStateMachine()
 {
-  return new MediaDecoderStateMachine(this, new WebMReader(this));
+  bool useFormatDecoder =
+    Preferences::GetBool("media.format-reader.webm", true);
+  nsRefPtr<MediaDecoderReader> reader = useFormatDecoder ?
+      static_cast<MediaDecoderReader*>(new MediaFormatReader(this, new WebMDemuxer(GetResource()))) :
+      new WebMReader(this);
+  return new MediaDecoderStateMachine(this, reader);
 }
 
 } // namespace mozilla
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index 0011dbe539a..4eae30299ea 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -480,6 +480,11 @@ pref("media.mediasource.format-reader.mp4", true);
 // Enable new MediaFormatReader architecture for plain mp4.
 pref("media.format-reader.mp4", true);
 
+// Enable new MediaFormatReader architecture for webm in MSE
+pref("media.mediasource.format-reader.webm", false);
+// Enable new MediaFormatReader architecture for plain webm.
+pref("media.format-reader.webm", false);
+
 #ifdef MOZ_WEBSPEECH
 pref("media.webspeech.recognition.enable", false);
 pref("media.webspeech.synth.enabled", false);