diff --git a/knowledge-base/window-themecolor.md b/knowledge-base/window-themecolor.md
new file mode 100644
index 000000000..85aec04d3
--- /dev/null
+++ b/knowledge-base/window-themecolor.md
@@ -0,0 +1,135 @@
+---
+title: Apply Window ThemeColor
+description: Learn how to apply background and color styles to the Telerik Window and Dialog components for Blazor in the same way as the removed ThemeColor parameter.
+type: troubleshooting
+page_title: How to Apply ThemeColor to Blazor Dialog and Window
+meta_title: How to Apply ThemeColor to Blazor Dialog and Window
+slug: window-kb-themecolor
+tags: telerik, blazor, window, styles
+ticketid: 1716488
+res_type: kb
+---
+
+## Environment
+
+<table>
+    <tbody>
+        <tr>
+            <td>Product</td>
+            <td>Window for Blazor, <br /> Dialog for Blazor</td>
+        </tr>
+        <tr>
+            <td>Version</td>
+            <td>14.0.0 and above</td>
+        </tr>
+    </tbody>
+</table>
+
+## Description
+
+After upgrading Telerik UI for Blazor to version 14 and above, the `ThemeColor` parameter of the Window and Dialog components is no longer available. This article shows how to achieve the previous component appearance.
+
+## Cause
+
+The [changes in the `ThemeColor` parameter availability and theme color values](slug:changes-in-14-0-0#themecolor-changes) are a result of a design revision. The removed parameters and values were no longer deemed appropriate or recommended for the Telerik UI for Blazor design language.
+
+## Solution
+
+To apply a theme color to a Window or Dialog component:
+
+1. Implement a CSS rule that applies `color` and `background-color` styles to `.k-window-titlebar`. The styles can use the built-in [Telerik CSS theme color variables](slug:themes-custom#setting-theme-variables). There is no need to override the variable values.
+    ````CSS.skip-repl
+    .window-primary .k-window-titlebar {
+        color: var(--kendo-color-on-primary);
+        background-color: var(--kendo-color-primary);
+    }
+    ````
+1. Set the respective custom CSS class (for example, `window-primary`) to the Window or Dialog `Class` parameter.
+    ````RAZOR.skip-repl
+    <TelerikWindow Class="window-primary" />
+    ````
+
+>caption Set Dialog and Window theme color with CSS
+
+````RAZOR
+<TelerikWindow @bind-Visible="@WindowVisible"
+               Class="@($"window-{ThemeColor}")"
+               Width="400px">
+    <WindowActions>
+        <WindowAction Name="Minimize" />
+        <WindowAction Name="Maximize" />
+        <WindowAction Name="Close" />
+    </WindowActions>
+    <WindowTitle>
+        Window Title
+    </WindowTitle>
+    <WindowContent>
+        <p>Apply theme color:</p>
+        <TelerikRadioGroup Data="@ThemeColors"
+                           @bind-Value="@ThemeColor"
+                           Layout="@RadioGroupLayout.Vertical" />
+    </WindowContent>
+</TelerikWindow>
+
+<TelerikDialog @ref="@DialogRef"
+               Class="@($"window-{ThemeColor}")"
+               @bind-Visible="@DialogVisible"
+               Width="400px">
+    <DialogTitle>Dialog Title</DialogTitle>
+    <DialogContent>
+        <p>Apply theme color:</p>
+        <TelerikRadioGroup Data="@ThemeColors"
+                           @bind-Value="@ThemeColor"
+                           Layout="@RadioGroupLayout.Vertical"
+                           OnChange="@(() => { DialogRef!.Refresh(); })" />
+    </DialogContent>
+</TelerikDialog>
+
+<style>
+    @foreach (var themeColor in ThemeColors)
+    {
+        @GetCssRuleForWindowThemeColor(themeColor)
+    }
+</style>
+
+<TelerikButton OnClick="@(() => WindowVisible = true)"
+               Visible="@(!WindowVisible && !DialogVisible)">
+    Open Window
+</TelerikButton>
+
+<TelerikButton OnClick="@(() => DialogVisible = true)"
+               Visible="@(!DialogVisible && !WindowVisible)">
+    Open Dialog
+</TelerikButton>
+
+@code {
+    private readonly string[] ThemeColors = new string[] { "primary", "secondary", "tertiary", "inverse", "info", "success", "warning", "error" };
+    private string ThemeColor { get; set; } = string.Empty;
+
+    private TelerikDialog? DialogRef;
+    private bool DialogVisible { get; set; }
+    private bool WindowVisible { get; set; } = true;
+
+    private string GetCssRuleForWindowThemeColor(string themeColor)
+    {
+        return
+            $".window-{themeColor} .k-window-titlebar" +
+            "{" +
+                $"color: var(--kendo-color-on-{themeColor});" +
+                $"background-color: var(--kendo-color-{themeColor});" +
+            "}";
+    }
+
+    protected override void OnInitialized()
+    {
+        ThemeColor = ThemeColors[0];
+
+        base.OnInitialized();
+    }
+}
+````
+
+## See Also
+
+* [Dialog Overview](slug:dialog-overview)
+* [Window Overview](slug:window-overview)
diff --git a/upgrade/breaking-changes/14-0-0.md b/upgrade/breaking-changes/14-0-0.md
index 3a2443440..dec3134ff 100644
--- a/upgrade/breaking-changes/14-0-0.md
+++ b/upgrade/breaking-changes/14-0-0.md
@@ -90,8 +90,8 @@ The following values of the `ThemeColor` parameter are removed from the followin
 The `ThemeColor` parameter is removed from:
 
 * Card. See how to [use the `Class` parameter to apply theme colors to Cards](slug:card-kb-replace-themecolor-parameter).
-* Dialog
-* Window
+* Dialog. See how to [use the `Class` parameter instead](slug:window-kb-themecolor).
+* Window. See how to [use the `Class` parameter instead](slug:window-kb-themecolor).
 * Popup edit settings
 
 ### OverlayThemeColor Parameter