BUG - Updating Modal via modal.objects results in the display of the updated objects in place of modal

[SultanOrazbayev]

ALL software version info

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Software Version Info

panel==1.6.0

Description of expected behavior and the observed behavior

Running the code below will show the modal window as expected. However, if the lines inside __update_modal are uncommented, then clicking the button inserts the modal contents into the main page and does not show the modal correctly. This bug prevents dynamic update of the modal contents.

Complete, minimal, self-contained example code that reproduces the issue

import param
from panel import Column, Modal, extension, template, widgets

extension("modal")


class TestApp(param.Parameterized):
    text = param.String(default="Hello, World!")
    slider = param.Number(default=0.0)

    def __init__(self, **params):
        super().__init__(**params)
        self.modal = Modal("TEST", widgets.TextInput(name="Text:", value=self.text), name="Basic FloatPanel", margin=20)
        self.toggle_button = widgets.Button(name="Toggle modal", button_type="primary")
        self.toggle_button.on_click(lambda event: self.__update_modal())

    def __update_modal(self):
        # self.modal.objects = [
        #     widgets.FloatSlider(name="Slider", value=self.slider),
        # ]
        self.modal.show()

    def __panel__(self):
        return Column(
            self.modal,
            self.toggle_button,
        )


test = TestApp()
app = template.VanillaTemplate(title="Basic Modal", main=[test])
app.show()