--- a/dom/media/platforms/wmf/WMFDecoderModule.cpp
+++ b/dom/media/platforms/wmf/WMFDecoderModule.cpp
@@ -210,18 +210,17 @@ WMFDecoderModule::Supports(const TrackIn
   if (MP4Decoder::IsH264(aTrackInfo.mMimeType) && WMFDecoderModule::HasH264()) {
     return true;
   }
   if (aTrackInfo.mMimeType.EqualsLiteral("audio/mpeg") &&
       CanCreateWMFDecoder<CLSID_CMP3DecMediaObject>()) {
     return true;
   }
   if (MediaPrefs::PDMWMFVP9DecoderEnabled()) {
-    if ((VPXDecoder::IsVP8(aTrackInfo.mMimeType) ||
-         VPXDecoder::IsVP9(aTrackInfo.mMimeType)) &&
+    if (VPXDecoder::IsVP9(aTrackInfo.mMimeType) &&
         ((gfxPrefs::PDMWMFAMDVP9DecoderEnabled() &&
           CanCreateWMFDecoder<CLSID_AMDWebmMfVp9Dec>()) ||
          CanCreateWMFDecoder<CLSID_WebmMfVpxDec>())) {
       return true;
     }
   }
 
   // Some unsupported codec.