From 6f1eb81cbf7a47b42436127bad2789d2f3946406 Mon Sep 17 00:00:00 2001
From: Christoph Wille <christoph.wille@gmail.com>
Date: Tue, 23 Jun 2026 06:35:51 +0200
Subject: [PATCH] Fix "Failed to decompile the assembly
 'Z:\net10.0-windows\ILSpy.dll': Object reference not set to an instance of an
 object."

---
 ILSpy/Languages/CSharpLanguage.cs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/ILSpy/Languages/CSharpLanguage.cs b/ILSpy/Languages/CSharpLanguage.cs
index 0d8f877f8..92731ed79 100644
--- a/ILSpy/Languages/CSharpLanguage.cs
+++ b/ILSpy/Languages/CSharpLanguage.cs
@@ -561,8 +561,7 @@ namespace ICSharpCode.ILSpy.Languages
 					entryStream.Position = 0;
 					fileName = handler.WriteResourceToFile(assembly, fileName, entryStream, context);
 					var item = new ProjectItemInfo(handler.EntryType, fileName) { PartialTypes = context.PartialTypes };
-					foreach (var (k, v) in context.AdditionalProperties)
-						item.AdditionalProperties.Add(k, v);
+					item = item.With(context.AdditionalProperties);
 					return new[] { item };
 				}
 				return base.WriteResourceToFile(fileName, resourceName, entryStream);