.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 bases on main branch in Winforms repo.