[Dark Mode] The color contrast is less than 3:1 for seleted treenode

[Zheng-Li01]

.NET version

9.0.0-rc.1.24414.1 + build private dll form winforms repo main branch

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 new feature Dark Mode: #11857

Issue description

The color contrast is less than 3:1 for seleted treenode in the DarkMode

Steps to reproduce

1. Create a WinForms .NET Core application with TreeView control.
2. Add some nodes for treeview1 control.
3. Enable DarkMode by Application.SetColorMode(SystemColorMode.Dark) in Program.cs file.
4. Run the application.
5. Selected the node, and then using the Accessibility Insight tool to observe the color contrast between selected node and background.

[dotnet-policy-service]

This issue is now marked as "help wanted", and we’re looking for a community volunteer to work on this issue. If we receive no interest in 180 days, we will close the issue. To learn more about how we handle feature requests, please see our documentation.

Happy Coding!