Update JavaScript support code snippet

colinrotherham · colinrotherham · commit 5da5dfe746e5 · 2025-05-20T17:51:49.000+01:00
diff --git a/docs/installation/installing-compiled.md b/docs/installation/installing-compiled.md
@@ -49,7 +49,7 @@ If you require any of this functionality, you should [install using npm](/docs/i
    Add the following JavaScript to the top of the `<body>` section of your page template:
 
    ```html
-   <script>document.body.className = ((document.body.className) ? document.body.className + ' js-enabled' : 'js-enabled');</script>
+   <script>document.body.className += ' js-enabled' + ('noModule' in HTMLScriptElement.prototype ? ' nhsuk-frontend-supported' : '');</script>
    ```
 
 4. Create pages using NHS.UK frontend
diff --git a/docs/installation/installing-with-npm.md b/docs/installation/installing-with-npm.md
@@ -74,7 +74,7 @@ You should include NHS.UK frontend JavaScript in your project to ensure that all
 Add the following JavaScript to the top of the `<body>` section of your page template:
 
 ```js
-document.body.className = ((document.body.className) ? document.body.className + ' js-enabled' : 'js-enabled');
+<script>document.body.className += ' js-enabled' + ('noModule' in HTMLScriptElement.prototype ? ' nhsuk-frontend-supported' : '');</script>
 ```
 
 ### Option 1: Include compiled JavaScript
diff --git a/packages/template.njk b/packages/template.njk
@@ -28,7 +28,7 @@
   </head>
 
   <body {% if bodyClasses %}class="{{ bodyClasses }}"{% endif %} {{- nhsukAttributes(bodyAttributes) }}>
-    <script>document.body.className = ((document.body.className) ? document.body.className + ' js-enabled' : 'js-enabled');</script>
+    <script>document.body.className += ' js-enabled' + ('noModule' in HTMLScriptElement.prototype ? ' nhsuk-frontend-supported' : '');</script>
     {% block bodyStart %}{% endblock %}
 
       {% block skipLink %}
