1 files changed, 1 insertions, 1 deletions
diff --git a/services/sync/tps/extensions/mozmill/resource/modules/assertions.js b/services/sync/tps/extensions/mozmill/resource/modules/assertions.js
index c9991acf0..c76f95747 100644
--- a/services/sync/tps/extensions/mozmill/resource/modules/assertions.js
+++ b/services/sync/tps/extensions/mozmill/resource/modules/assertions.js
@@ -659,7 +659,7 @@ Expect.prototype.waitFor = function Expect_waitFor(aCallback, aMessage, aTimeout
     Assert.prototype.waitFor.apply(this, arguments);
   }
   catch (ex) {
-    if (!ex instanceof errors.AssertionError) {
+    if (!(ex instanceof errors.AssertionError)) {
       throw ex;
     }
     message = ex.message;