diff --git a/storage/mozStoragePrivateHelpers.cpp b/storage/mozStoragePrivateHelpers.cpp
index 77e1292fd52ae..91924204f107c 100644
--- a/storage/mozStoragePrivateHelpers.cpp
+++ b/storage/mozStoragePrivateHelpers.cpp
@@ -117,7 +117,7 @@ checkAndLogStatementPerformance(sqlite3_stmt *aStatement)
 nsIVariant *
 convertJSValToVariant(
   JSContext *aCtx,
-  JS::Value aValue)
+  const JS::Value& aValue)
 {
   if (aValue.isInt32())
     return new IntegerVariant(aValue.toInt32());
diff --git a/storage/mozStoragePrivateHelpers.h b/storage/mozStoragePrivateHelpers.h
index 529e72b0e681f..cfec6ff7f822d 100644
--- a/storage/mozStoragePrivateHelpers.h
+++ b/storage/mozStoragePrivateHelpers.h
@@ -65,7 +65,7 @@ void checkAndLogStatementPerformance(sqlite3_stmt *aStatement);
  * @return the variant if conversion was successful, nullptr if conversion
  *         failed.  The caller is responsible for addref'ing if non-null.
  */
-nsIVariant *convertJSValToVariant(JSContext *aCtx, JS::Value aValue);
+nsIVariant *convertJSValToVariant(JSContext *aCtx, const JS::Value& aValue);
 
 /**
  * Convert a provided nsIVariant implementation to our own thread-safe