diff --git a/www/js/app.js b/www/js/app.js
index ff3379cf..56e2053f 100644
--- a/www/js/app.js
+++ b/www/js/app.js
@@ -1087,7 +1087,7 @@ define(['jquery', 'zimArchiveLoader', 'uiUtil', 'util', 'cache', 'images', 'sett
             if (this.value === 'serviceworker') {
                 if (params.manipulateImages) document.getElementById('manipulateImagesCheck').click();
                 if (params.allowHTMLExtraction) document.getElementById('allowHTMLExtractionCheck').click();
-                if (!window.location.protocol === 'ms-appx-web:') uiUtil.systemAlert(
+                if (window.location.protocol !== 'ms-appx-web:') uiUtil.systemAlert(
                     'Please note that we have disabled Image manipulation and/or Breakout link as these options can interfere with ZIMs that have active content. You may turn them back on, but be aware that they are only recommended for use with Wikimedia ZIMs.'
                 );
             }