Anchors right_target not working properly

[VitoR-InA]

Expected behaviour
Two buttons: LEFT and RIGHT should be positioned according to their parent element. But right_target does not work correctly.

Screenshots

Code

import pygame
from pygame import Rect
from pygame import Window

from pygame_gui import UIManager
from pygame_gui.elements import UIButton, UIPanel


class test(Window):
    def __init__(self):
        pygame.init()
        super().__init__(fullscreen_desktop = True)
        self.clock = pygame.time.Clock()
        self.screen = self.get_surface()
        self.manager = UIManager(self.size)
        
        parent_panel = UIPanel(Rect(self.size[0] / 2 - 250, self.size[1] / 2 - 100, 500, 200), manager = self.manager)
        
        child_rect = Rect()
        child_rect.size = (200, 200)

        child_rect.topright = (-10, self.size[1] / 2 - 100)
        child_left = UIButton(child_rect, "RIGHT", self.manager, anchors = {"right_target":parent_panel})

        child_rect.topleft = (10, self.size[1] / 2 - 100)
        child_right = UIButton(child_rect, "LEFT", self.manager, anchors = {"left_target":parent_panel})

    def run(self):
        running = True
        while running:
            td = self.clock.tick(120) / 1000.0
            for event in pygame.event.get():
                self.manager.process_events(event)
                if event.type == pygame.QUIT: running = False
            
            self.screen.fill("#141414")
            self.manager.update(td)
            self.manager.draw_ui(self.screen)
            self.flip()
                

if __name__ == "__main__":
    test().run()

Platform and software (please complete the following information):

• OS: Windows 11
• Pygame GUI version 0.6.12
• Pygame version 2.5.2