docs: add kb on missing kendo ui theme error (#1888)

Author: petar-i-todorov

knowledge-base/typeerror-cannot-read-properties-undefined-reading-wrapper.md

@@ -0,0 +1,43 @@
+---
+title: TypeError Cannot read properties of undefined (reading 'wrapper') in HTML5-based report viewers
+description: Learn how to resolve the TypeError about 'wrapper' in HTML5-based report viewers when AI-powered insights dialog fails to initialize.
+type: troubleshooting
+page_title: TypeError Cannot read properties of undefined (reading 'wrapper') in HTML5-based report viewers
+meta_title: TypeError Cannot read properties of undefined (reading 'wrapper') in HTML5-based report viewers
+slug: cannot-read-properties-of-undefined-reading-wrapper
+tags: reporting, html5 viewer, kendo ui, theme, ai insights, wrapper
+res_type: kb
+---
+
+## Environment
+
+<table>
+    <tbody>
+        <tr>
+            <td> Product </td>
+            <td> Reporting </td>
+        </tr>
+        <tr>
+            <td> Version </td>
+            <td> 19.2.25.1001 </td>
+        </tr>
+    </tbody>
+</table>
+
+## Description
+
+When initializing the HTML5 Report Viewer, a `TypeError: Cannot read properties of undefined (reading 'wrapper')` error appears in the browser console, preventing the report viewer from loading properly.
+
+## Cause
+
+This error occurs when a [Sass-based Kendo UI theme](https://www.telerik.com/design-system/docs/themes/get-started/introduction/) is missing from the page. The report viewer requires proper Kendo UI styling to initialize correctly.
+
+## Solution
+
+Include a valid Kendo UI theme in your page by adding a CSS reference such as:
+
+````html
+<link rel="stylesheet" href="https://kendo.cdn.telerik.com/themes/10.2.0/default/default-ocean-blue.css" />
+````
+
+For more information about available themes, see [Telerik and Kendo UI Themes Introduction](https://www.telerik.com/design-system/docs/themes/get-started/introduction/).