diff --git a/src/modules/cmdpal/Microsoft.CmdPal.UI/Helpers/BindTransformers.cs b/src/modules/cmdpal/Microsoft.CmdPal.UI/Helpers/BindTransformers.cs
index d0c3652193..22e68fdb4a 100644
--- a/src/modules/cmdpal/Microsoft.CmdPal.UI/Helpers/BindTransformers.cs
+++ b/src/modules/cmdpal/Microsoft.CmdPal.UI/Helpers/BindTransformers.cs
@@ -27,4 +27,7 @@ internal static class BindTransformers
 
     public static Visibility VisibleWhenAny(bool value1, bool value2)
         => (value1 || value2) ? Visibility.Visible : Visibility.Collapsed;
+
+    public static Thickness BottomBorderThicknessWhenAll(bool value1, bool value2)
+        => value1 && value2 ? new Thickness(0, 0, 0, 1) : new Thickness(0);
 }
diff --git a/src/modules/cmdpal/Microsoft.CmdPal.UI/Pages/ShellPage.xaml b/src/modules/cmdpal/Microsoft.CmdPal.UI/Pages/ShellPage.xaml
index 4333a20867..9745c92490 100644
--- a/src/modules/cmdpal/Microsoft.CmdPal.UI/Pages/ShellPage.xaml
+++ b/src/modules/cmdpal/Microsoft.CmdPal.UI/Pages/ShellPage.xaml
@@ -206,7 +206,7 @@
                 HorizontalAlignment="Stretch"
                 VerticalAlignment="Stretch"
                 BorderBrush="{ThemeResource CmdPal.TopBarBorderBrush}"
-                BorderThickness="0,0,0,1">
+                BorderThickness="{x:Bind h:BindTransformers.BottomBorderThicknessWhenAll(ViewModel.IsSearchBoxVisible, ExpandedMode), Mode=OneWay}">
                 <Grid.ColumnDefinitions>
                     <ColumnDefinition Width="Auto" />
                     <ColumnDefinition Width="*" />
@@ -596,7 +596,6 @@
                     <VisualState.Setters>
                         <Setter Target="SearchBox.IsEnabled" Value="False" />
                         <Setter Target="SearchBox.Opacity" Value="0" />
-                        <Setter Target="TopBarGrid.BorderBrush" Value="Transparent" />
                     </VisualState.Setters>
                 </VisualState>
             </VisualStateGroup>