How do I put a TWebPanel that is taller than the screen height into a TWebScrollBox and have scrolls generated?

I want to put a TWebPanel with a height greater than the screen size inside a TWebScrollBox box and have the scroll appear on the right and bottom, how can I do that?

If I understood your question well, here is a sample project. (5.4 KB)

On the main screen, it works like the sample project.
However, it doesn't work on the dialog form (subform) that I created on the main form. Please tell me how to do it.

Please isolate this into a test project with source code so we know exactly how you create the subform and can investigate here.