Windows: Upgrade solution itself
diff --git a/windows/vs2019/xz_win.sln b/windows/vs2019/xz_win.sln
index ba49f3e..c65cd3e 100644
--- a/windows/vs2019/xz_win.sln
+++ b/windows/vs2019/xz_win.sln
@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 15
-VisualStudioVersion = 15.0.26430.14
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.28803.202
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "liblzma", "liblzma.vcxproj", "{12728250-16EC-4DC6-94D7-E21DD88947F8}"
 EndProject
@@ -45,4 +45,7 @@
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {78887FAE-FC02-4B67-A8DB-DC7863496039}
+	EndGlobalSection
 EndGlobal