expand_y breaks Push()

FreeSimpleGUI version 5.2.0.post1
Python version 3.10.12 on Ubuntu 22.04

I have had difficulty making the Push() function work as the documentation describes. The following code shows the issue. The intent is to have two columns, one containing a Listbox of fruit justified to the left edge of the window and the other containing a Listbox of playing cards justified to the right edge of the window.

When both columns have expand_y = True, the resulting GUI has both columns justified to the left despite having a Push() between them in the window layout. If I comment out the expand_y = True line from the Cards Column (just below the line # This breaks Push()), then suddenly the Push() works and the Cards Column is justified to the right edge. Of course, it is no longer extended vertically the way I want it.

Sample code:

import FreeSimpleGUI as sg

default_font = ("Arial", 16)

### FRUIT COLUMN ###
fruit_header = sg.Text('Fruit', justification = 'center', expand_x = True)
fruit_listbox = sg.Listbox(values = ['apple', 'banana', 'clementine', 'durian'],
                           key = '-FRUIT-', size = (40, None) )

fruit_column = sg.Column( [ [fruit_header], [fruit_listbox] ],
                          expand_y=True,
                          background_color = 'orange')

### CARDS COLUMN ###
cards_header = sg.Text('Cards', justification = 'center', expand_x = True)
cards_listbox = sg.Listbox(values = ['King', 'Queen', 'Eight', 'Joker'],
                           key = '-CARDS-', size = (40, None) )

cards_column = sg.Column( [ [cards_header], [cards_listbox] ],
                          # This breaks Push()
                          expand_y = True,
                          background_color = 'purple')

layout = [ [fruit_column, sg.Push(), cards_column] ]

# Create the Window
window = sg.Window('Justification Test', layout, resizable=True, finalize=True,
                   size=sg.Window.get_screen_size(), location=(0,0),
                   font = default_font)

window.bind('<Escape>', '-ESCAPE-')

# Event Loop to process "events" and get the "values" of the inputs
while True:

    event, values = window.read()
    if event in (sg.WIN_CLOSED, '-ESCAPE-'):
        break

window.close()

Is there a way to have both columns extend the entire height of the window while also being justified to opposite edges horizontally?

Start by running the supplied Python sample on FreeSimpleGUI 5.2.0.post1 and inspect the Push() and Column() layout behavior when both columns use expand_y=True. Verify whether the columns can remain vertically expanded while Push() separates them horizontally; done means the fruit column is left-aligned, the cards column is right-aligned, and both fill the window height.