diff --git a/src/Avalonia.Controls/SystemDialog.cs b/src/Avalonia.Controls/SystemDialog.cs
index ee41b94b5a..d2b893df37 100644
--- a/src/Avalonia.Controls/SystemDialog.cs
+++ b/src/Avalonia.Controls/SystemDialog.cs
@@ -18,7 +18,7 @@ namespace Avalonia.Controls
/// Gets or sets a collection of filters which determine the types of files displayed in an
/// or an .
///
- public List? Filters { get; set; } = new List();
+ public List Filters { get; set; } = new List();
///
/// Gets or sets initial file name that is displayed when the dialog is opened.