diff --git a/common/modules/base.jsm b/common/modules/base.jsm
index 31a5e139..e4439df7 100644
--- a/common/modules/base.jsm
+++ b/common/modules/base.jsm
@@ -4,8 +4,9 @@
 // given in the LICENSE.txt file included with this file.
 "use strict";
 
-if (!JSMLoader)
+if (!JSMLoader || JSMLoader.bump != 1)
     var JSMLoader = {
+        bump: 1,
         builtin: Components.utils.Sandbox(this),
         factories: [],
         globals: {},