--- a/layout/style/Loader.cpp
+++ b/layout/style/Loader.cpp
@@ -1881,18 +1881,17 @@ Loader::DoSheetComplete(SheetLoadData* a
     // Remove the data from the list of loading datas
     if (aLoadData->mIsLoading) {
       URIPrincipalReferrerPolicyAndCORSModeHashKey key(aLoadData->mURI,
                                          aLoadData->mLoaderPrincipal,
                                          aLoadData->mSheet->GetCORSMode(),
                                          aLoadData->mSheet->GetReferrerPolicy());
 #ifdef DEBUG
       SheetLoadData *loadingData;
-      // XXXheycam Temporarily downgrade this assertion (bug 1314045).
-      NS_ASSERTION_STYLO_WARNING(
+      NS_ASSERTION(
         mSheets->mLoadingDatas.Get(&key, &loadingData) &&
         loadingData == aLoadData,
         "Bad loading table");
 #endif
 
       mSheets->mLoadingDatas.Remove(&key);
       aLoadData->mIsLoading = false;
     }