Menus should follow dark theme

When the Cantabile UI is configured to use the dark theme, I’ve observed the following:

  1. In full-screen mode, the main application menu bar appears dark as expected, but drop-down and context menus are still light.
  2. In non-full-screen mode, the main application menu bar, drop-down menus, and context menus are all light.

All application menu bars, drop-down menus, and context menus should consistently follow the dark theme under all circumstances.

This is under version 4.0 build 4214 running under Windows 11 build 22631.4825.