How to select values ​​in multiple listbox Tkinter?

Question

Python

There are three listboxes, values ​​are taken from each. Unfortunately, when I select something in one, the selection disappears in the other. How to make it so that you can select items in three listboxes at once?

Answer 1

Based on the experience of using TKinter and GTK, I would choose the second one - it has fewer problems in this regard.
As I understand it, the selection ceases to be visible when the focus is lost, but is it generally preserved?
Most likely it is necessary to intercept the event when the mouse left the control (or loss of focus) and change the background of the selected elements (or highlight them differently). A crutch of course, but I think the problem is within TK itself.