From 287b5b71553c8b883323c463bd045ccbe855bcc2 Mon Sep 17 00:00:00 2001
From: Dimo Dimov <961014+dimodi@users.noreply.github.com>
Date: Thu, 1 Sep 2022 17:05:35 +0300
Subject: [PATCH] docs(common): Add KB for broken CSS styles after upgrade

---
 ...erties-of-null-reading-addeventlistener.md |  2 +
 .../common-upgrade-breaks-css-theme-styles.md | 51 +++++++++++++++++++
 2 files changed, 53 insertions(+)
 create mode 100644 knowledge-base/common-upgrade-breaks-css-theme-styles.md

diff --git a/knowledge-base/common-cannot-read-properties-of-null-reading-addeventlistener.md b/knowledge-base/common-cannot-read-properties-of-null-reading-addeventlistener.md
index 47d6e9a697..f6474a9140 100644
--- a/knowledge-base/common-cannot-read-properties-of-null-reading-addeventlistener.md
+++ b/knowledge-base/common-cannot-read-properties-of-null-reading-addeventlistener.md
@@ -64,4 +64,6 @@ The Blazor framework should normally take care of caching issues with static ass
 
 ## See Also
 
+* [Telerik UI for Blazor version upgrade steps]({%slug upgrade-tutorial%})
 * [Troubleshooting JavaScript Errors]({%slug troubleshooting-js-errors%})
+* [Fix styling issues after component version update](%slug common-kb-upgrade-breaks-css-theme-styles%)
diff --git a/knowledge-base/common-upgrade-breaks-css-theme-styles.md b/knowledge-base/common-upgrade-breaks-css-theme-styles.md
new file mode 100644
index 0000000000..d97faccb83
--- /dev/null
+++ b/knowledge-base/common-upgrade-breaks-css-theme-styles.md
@@ -0,0 +1,51 @@
+---
+title: Version Update Breaks UI Component Styling
+description: How to resolve broken CSSS theme styles after version upgrade of Telerik UI for Blazor
+type: troubleshooting
+page_title: Version Update Breaks UI Component Styling
+slug: common-kb-upgrade-breaks-css-theme-styles
+position: 
+tags: css, styling, upgrade
+ticketid: 1541420, 1564763, 1575968, 1578100
+res_type: kb
+---
+
+## Environment
+
+<table>
+    <tbody>
+        <tr>
+          <td>Product</td>
+          <td>Telerik UI for Blazor</td>
+        </tr>
+    </tbody>
+</table>
+
+## Description
+
+The UI components do not render and look properly after version update.
+
+How to resolve UI (styling) issues after NuGet package version upgrade? Where do I get the new theme CSS stylesheet?
+
+## Steps to Reproduce
+
+Upgrade the Telerik UI for Blazor version (NuGet package). The component styling breaks. If the previous version is restored, the styling is OK.
+
+## Cause\Possible Cause(s)
+
+The application is using an outdated CSS theme or swatch.
+
+## Solution
+
+To resolve the problem, follow the [recommended UI for Blazor upgrade procedure]({%slug upgrade-tutorial%}):
+
+* If using the [Telerik **CDN**]({%slug getting-started/what-you-need%}#cdn) - update the [stylesheet file URL]({%slug themes-swatch-distribution%}) to the correct version.
+* If using a **local** CSS file in `wwwroot` - replace the stylesheet with a compatible one. If the application is using a [**custom theme**, then recreate it]({%slug themes-custom%}#import-custom-theme).
+* If using **static assets** from the NuGet package - clear the browser cache.
+
+A version update might break custom application CSS styles that are outside the Telerik theme. In this case, then check if the component HTML rendering or CSS classes have changed, and adjust the custom CSS code.
+
+## See Also
+
+* [Telerik UI for Blazor version upgrade steps]({%slug upgrade-tutorial%})
+* [Troubleshooting JavaScript errors after version upgrade]({%slug common-kb-cannot-read-properties-of-null-reading-addeventlistener%})