### .NET version The latest main branch of Winforms repo ### Did it work in .NET Framework? No ### Did it work in any of the earlier releases of .NET Core or .NET 5+? This is a regression issue, can reproduce on release/10.0-preview6 branch, cannot reproduce on release/10.0-preview5 branch ### Issue description The extra number displayed on Name & Text Propeties for the ToolStrip control **main branch:**  **release/10.0-preview5**  **net481**  ### Steps to reproduce Test sample: [DemoConsole](https://github.com/dotnet/winforms/tree/main/src/System.Windows.Forms/tests/IntegrationTests/DesignSurface/DemoConsole) bases on main branch in Winforms repo.