diff --git a/modules/ui/intro/building.js b/modules/ui/intro/building.js
index 759f054c8..374f775ee 100644
--- a/modules/ui/intro/building.js
+++ b/modules/ui/intro/building.js
@@ -328,8 +328,9 @@ export function uiIntroBuilding(context, reveal) {
 
 
     function addTank() {
-        var tooltip = reveal('button.add-area',
-            t('intro.buildings.add_tank', { button: icon('#icon-area', 'pre-text') }));
+        reveal('button.add-area',
+            t('intro.buildings.add_tank', { button: icon('#icon-area', 'pre-text') })
+        );
 
         tankId = null;
         context.history().reset('doneSquare');