Two issues: tab key does not work in MainWindow elements and there's an erroneous overlay

[jbiel]

I'm playing around with this library (it looks like the best option for building a small Windows app) and found two issues with it in my testing. The parent fork does not demonstrate these issues.

• The tab key cannot be used to move between elements in a main window
• There is an "overlay" bar at the top of the MainWindow. This happens in most of the stock examples (which use MainWindow) that I've tested.

I put together a reproduction repository with the full code, go.mod, etc. that was used for the tests.

Thanks for maintenance of this project and for taking a look!

Demonstration

The video below was run (go run .) on Windows Server 2022 using Go 1.24.1 via RDP.

https://github.com/user-attachments/assets/ae83a334-c4f2-40ca-a4b8-7bcf86703578

The video below was run (GOOS=windows go build -o test.exe . && wine64 test.exe) locally on Linux.

https://github.com/user-attachments/assets/487a9ebf-0809-45fc-b71d-0e3884b6c29c