mousewheel on scrollable frame changes dropdowns while hovering.

[rambit]

Describe the bug
Scrolling the mouse with mousewheel on the scrollable frame to the right (Properties pane, Appearance tab) changes the properties of dropdowns when hovering above them, as can be seen in this recording.

mousewheel.webm

You'd need to remember what the dropdown was before the mistake, because you have to change it back manually, or quit without saving.

My best guess is that it derives from tkscrolledframe.py and more guessing that it could be bound around line 293?

Environment

• OS: Ubuntu 23.04
• Python version: 3.11.2
• Pygubu version: pygubu 0.30
• Designer version: pygubu-designer 0.35