Fixes #1135

Author: batzen

Changelog.md

@@ -6,6 +6,7 @@
 
   - [#1133](../../issues/1133) - Fixing binding path to attached property for simplified ControlTemplates (thanks @dcm99)
   - [#1134](../../issues/1134) - Selected Tab on first render has a black border
+  - [#1135](../../issues/1135) - Black line between Ribbon and Window (when using a colorful theme)
 
 ## 10.0.0
 

Fluent.Ribbon/Themes/RibbonWindow.xaml

@@ -1,4 +1,4 @@
-<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:Fluent="clr-namespace:Fluent"
                     xmlns:controlzex="urn:controlzex"
@@ -23,7 +23,8 @@
                                HorizontalAlignment="Stretch"
                                VerticalAlignment="Top"
                                Background="{TemplateBinding TitleBackground}"
-                               LastChildFill="True">
+                               LastChildFill="True"
+                               Margin="0 0 0 -1">
                         <Image x:Name="PART_Icon"
                                Width="16"
                                Height="16"