[Tkinter] MenuBar hidden when new window opens

[john8888]

Clicking "File" shows New/Open:

   

Then clicking Open opens a small panel but hides the New/Open

   

Yes, the list can be reopened by clicking on File again but it would be nice if this list stayed open. If that's the way tkinter works that's fine but I thought I might be missing something.

Thanks, and sorry about the formatting.