1 files changed, 20 insertions, 0 deletions
diff --git a/release-notes/7.0/preview/api-diff/preview6/Microsoft.WindowsDesktop.App/7.0-preview6_System.Windows.Forms.Design.md b/release-notes/7.0/preview/api-diff/preview6/Microsoft.WindowsDesktop.App/7.0-preview6_System.Windows.Forms.Design.md
new file mode 100644
index 00000000..1c60c773
--- /dev/null
+++ b/release-notes/7.0/preview/api-diff/preview6/Microsoft.WindowsDesktop.App/7.0-preview6_System.Windows.Forms.Design.md
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+# System.Windows.Forms.Design
+
+``` diff
+ namespace System.Windows.Forms.Design {
+     [ToolboxItemAttribute(false)]
+     public class ComponentEditorForm : Form {
+         [BrowsableAttribute(false)]
+         [EditorBrowsableAttribute(1)]
+-        public new event EventHandler AutoSizeChanged;
++        public new event EventHandler? AutoSizeChanged;
+-        protected virtual void OnSelChangeSelector(object source, TreeViewEventArgs e);
++        protected virtual void OnSelChangeSelector(object? source, TreeViewEventArgs e);
+-        public virtual DialogResult ShowForm(IWin32Window owner);
++        public virtual DialogResult ShowForm(IWin32Window? owner);
+-        public virtual DialogResult ShowForm(IWin32Window owner, int page);
++        public virtual DialogResult ShowForm(IWin32Window? owner, int page);
+     }
+ }
+```
+