--- a/widget/GfxInfoBase.cpp
+++ b/widget/GfxInfoBase.cpp
@@ -155,17 +155,18 @@ GetPrefNameForFeature(int32_t aFeature)
     case nsIGfxInfo::FEATURE_WEBRTC_HW_ACCELERATION_DECODE:
       name = BLACKLIST_PREF_BRANCH "webrtc.hw.acceleration.decode";
       break;
     case nsIGfxInfo::FEATURE_CANVAS2D_ACCELERATION:
       name = BLACKLIST_PREF_BRANCH "canvas2d.acceleration";
       break;
     case nsIGfxInfo::FEATURE_VP8_HW_DECODE:
     case nsIGfxInfo::FEATURE_VP9_HW_DECODE:
-      // We don't provide prefs for this features.
+    case nsIGfxInfo::FEATURE_DX_INTEROP2:
+      // We don't provide prefs for these features.
       break;
     default:
       MOZ_ASSERT_UNREACHABLE("Unexpected nsIGfxInfo feature?!");
       break;
   }
 
   return name;
 }