diff --git a/public/activity_3/main-script.js b/public/activity_3/main-script.js
index 2327941bf6609700d2a083df789a5b3bac1bc346..2be91f846d43086ffeea575d565d0737b2737675 100644
--- a/public/activity_3/main-script.js
+++ b/public/activity_3/main-script.js
@@ -96,7 +96,7 @@ init_canvas()
 
 function enableManual() {
   manual_enabled = true;
-  alert("Augmenter/diminuer la puissance : 'Haut/Bas'");
+  //alert("Augmenter/diminuer la puissance : 'Haut/Bas'");
 }
 
 document.addEventListener('keydown', function(event) {