--- a/dom/media/MediaPrefs.h
+++ b/dom/media/MediaPrefs.h
@@ -133,17 +133,16 @@ private:
 #ifdef MOZ_FFVPX
   DECL_MEDIA_PREF("media.ffvpx.enabled",                      PDMFFVPXEnabled, bool, true);
 #endif
 #ifdef XP_WIN
   DECL_MEDIA_PREF("media.wmf.enabled",                        PDMWMFEnabled, bool, true);
   DECL_MEDIA_PREF("media.wmf.skip-blacklist",                 PDMWMFSkipBlacklist, bool, false);
   DECL_MEDIA_PREF("media.decoder-doctor.wmf-disabled-is-failure", DecoderDoctorWMFDisabledIsFailure, bool, false);
   DECL_MEDIA_PREF("media.wmf.vp9.enabled",                    PDMWMFVP9DecoderEnabled, bool, true);
-  DECL_MEDIA_PREF("media.wmf.amd.vp9.enabled",                PDMWMFAMDVP9DecoderEnabled, bool, true);
   DECL_MEDIA_PREF("media.wmf.decoder.thread-count",           PDMWMFThreadCount, int32_t, -1);
   DECL_MEDIA_PREF("media.wmf.allow-unsupported-resolutions",  PDMWMFAllowUnsupportedResolutions, bool, false);
 #endif
   DECL_MEDIA_PREF("media.decoder.fuzzing.enabled",            PDMFuzzingEnabled, bool, false);
   DECL_MEDIA_PREF("media.decoder.fuzzing.video-output-minimum-interval-ms", PDMFuzzingInterval, uint32_t, 0);
   DECL_MEDIA_PREF("media.decoder.fuzzing.dont-delay-inputexhausted", PDMFuzzingDelayInputExhausted, bool, true);
   DECL_MEDIA_PREF("media.decoder.recycle.enabled",            MediaDecoderCheckRecycling, bool, false);
   DECL_MEDIA_PREF("media.decoder.skip-to-next-key-frame.enabled", MFRSkipToNextKeyFrameEnabled, bool, true);

--- a/dom/media/platforms/wmf/WMFDecoderModule.cpp
+++ b/dom/media/platforms/wmf/WMFDecoderModule.cpp
@@ -10,16 +10,17 @@
 #include "MP4Decoder.h"
 #include "MediaInfo.h"
 #include "MediaPrefs.h"
 #include "VPXDecoder.h"
 #include "WMF.h"
 #include "WMFAudioMFTManager.h"
 #include "WMFMediaDataDecoder.h"
 #include "WMFVideoMFTManager.h"
+#include "gfxPrefs.h"
 #include "mozilla/DebugOnly.h"
 #include "mozilla/Maybe.h"
 #include "mozilla/Services.h"
 #include "mozilla/StaticMutex.h"
 #include "mozilla/WindowsVersion.h"
 #include "mozilla/gfx/gfxVars.h"
 #include "nsAutoPtr.h"
 #include "nsComponentManagerUtils.h"
@@ -259,17 +260,17 @@ WMFDecoderModule::Supports(const TrackIn
   }
   if (aTrackInfo.mMimeType.EqualsLiteral("audio/mpeg") &&
       CanCreateWMFDecoder<CLSID_CMP3DecMediaObject>()) {
     return true;
   }
   if (MediaPrefs::PDMWMFVP9DecoderEnabled()) {
     if ((VPXDecoder::IsVP8(aTrackInfo.mMimeType) ||
          VPXDecoder::IsVP9(aTrackInfo.mMimeType)) &&
-        ((MediaPrefs::PDMWMFAMDVP9DecoderEnabled() &&
+        ((gfxPrefs::PDMWMFAMDVP9DecoderEnabled() &&
           CanCreateWMFDecoder<CLSID_AMDWebmMfVp9Dec>()) ||
          CanCreateWMFDecoder<CLSID_WebmMfVpxDec>())) {
       return true;
     }
   }
 
   // Some unsupported codec.
   return false;

--- a/dom/media/platforms/wmf/WMFVideoMFTManager.cpp
+++ b/dom/media/platforms/wmf/WMFVideoMFTManager.cpp
@@ -605,17 +605,17 @@ WMFVideoMFTManager::InitInternal()
 {
   mUseHwAccel = false; // default value; changed if D3D setup succeeds.
   bool useDxva = InitializeDXVA();
 
   RefPtr<MFTDecoder> decoder;
 
   HRESULT hr;
   if (mStreamType == VP9 && useDxva && mCheckForAMDDecoder &&
-      MediaPrefs::PDMWMFAMDVP9DecoderEnabled()) {
+      gfxPrefs::PDMWMFAMDVP9DecoderEnabled()) {
     if ((decoder = LoadAMDVP9Decoder())) {
       mAMDVP9InUse = true;
     }
   }
   if (!decoder) {
     mCheckForAMDDecoder = false;
     mAMDVP9InUse = false;
     decoder = new MFTDecoder();

--- a/gfx/thebes/gfxPrefs.h
+++ b/gfx/thebes/gfxPrefs.h
@@ -663,16 +663,17 @@ private:
 #ifdef XP_WIN
   DECL_GFX_PREF(Live, "media.windows-media-foundation.allow-d3d11-dxva", PDMWMFAllowD3D11, bool, true);
   DECL_GFX_PREF(Live, "media.windows-media-foundation.max-dxva-videos", PDMWMFMaxDXVAVideos, uint32_t, 8);
   DECL_GFX_PREF(Live, "media.windows-media-foundation.use-nv12-format", PDMWMFUseNV12Format, bool, true);
   DECL_GFX_PREF(Once, "media.windows-media-foundation.use-sync-texture", PDMWMFUseSyncTexture, bool, true);
   DECL_GFX_PREF(Live, "media.wmf.low-latency.enabled", PDMWMFLowLatencyEnabled, bool, false);
   DECL_GFX_PREF(Live, "media.wmf.skip-blacklist", PDMWMFSkipBlacklist, bool, false);
   DECL_GFX_PREF(Live, "media.wmf.deblacklisting-for-telemetry-in-gpu-process", PDMWMFDeblacklistingForTelemetryInGPUProcess, bool, false);
+  DECL_GFX_PREF(Live, "media.wmf.amd.vp9.enabled", PDMWMFAMDVP9DecoderEnabled, bool, true);
 #endif
 
   // These affect how line scrolls from wheel events will be accelerated.
   DECL_GFX_PREF(Live, "mousewheel.acceleration.factor",        MouseWheelAccelerationFactor, int32_t, -1);
   DECL_GFX_PREF(Live, "mousewheel.acceleration.start",         MouseWheelAccelerationStart, int32_t, -1);
 
   // This affects whether events will be routed through APZ or not.
   DECL_GFX_PREF(Live, "mousewheel.system_scroll_override_on_root_content.enabled",