1 files changed, 1 insertions, 1 deletions
diff --git a/gfx/layers/apz/test/mochitest/helper_hittest_iframe_perspective-2.html b/gfx/layers/apz/test/mochitest/helper_hittest_iframe_perspective-2.html
index 9838a02aa9..b6128aaa87 100644
--- a/gfx/layers/apz/test/mochitest/helper_hittest_iframe_perspective-2.html
+++ b/gfx/layers/apz/test/mochitest/helper_hittest_iframe_perspective-2.html
@@ -44,7 +44,7 @@ async function test() {
       }
     });
 
-    window.addEventListener("mousedown", event => {
+    window.addEventListener("mousedown", () => {
       ok(true, "Parent document should have received mouse-down");
       resolve();
     });