From 658ff21d0ff97cac034ff416b4f73d948fc71aff Mon Sep 17 00:00:00 2001
From: Dan Walmsley <dan@walms.co.uk>
Date: Fri, 30 Nov 2018 14:03:00 +0000
Subject: [PATCH] fix border thickness being added to non-decorated windows.

---
 src/Windows/Avalonia.Win32/WindowImpl.cs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/Windows/Avalonia.Win32/WindowImpl.cs b/src/Windows/Avalonia.Win32/WindowImpl.cs
index e49eb5be9f..932cb4a9d0 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.cs
@@ -149,7 +149,11 @@ namespace Avalonia.Win32
             if (value != ClientSize)
             {
                 value *= Scaling;
-                value += BorderThickness;
+
+                if (_decorated)
+                {
+                    value += BorderThickness;
+                }
 
                 UnmanagedMethods.SetWindowPos(
                     _hwnd,