Show "Loading..." for extra networks when displaying for the first time

            with gr.Tab(page.title, id=page_id):

                elem_id = f"{tabname}_{page_id}_cards_html"

                page_elem = gr.HTML('', elem_id=elem_id)

                page_elem = gr.HTML('Loading...', elem_id=elem_id)

                ui.pages.append(page_elem)

                page_elem.change(fn=lambda: None, _js='function(){applyExtraNetworkFilter(' + json.dumps(tabname) + '); return []}', inputs=[], outputs=[])

    def toggle_visibility(is_visible):

        is_visible = not is_visible

        if is_visible and not ui.pages_contents:

        return is_visible, gr.update(visible=is_visible), gr.update(variant=("secondary-down" if is_visible else "secondary"))

    def fill_tabs(is_empty):

        """Creates HTML for extra networks' tabs when the extra networks button is clicked for the first time."""

        if not ui.pages_contents:

            refresh()

        return is_visible, gr.update(visible=is_visible), gr.update(variant=("secondary-down" if is_visible else "secondary")), *ui.pages_contents

        if is_empty:

            return True, *ui.pages_contents

        return True, *[gr.update() for _ in ui.pages_contents]

    state_visible = gr.State(value=False)

    button.click(fn=toggle_visibility, inputs=[state_visible], outputs=[state_visible, container, button, *ui.pages])

    button.click(fn=toggle_visibility, inputs=[state_visible], outputs=[state_visible, container, button], show_progress=False)

    state_empty = gr.State(value=True)

    button.click(fn=fill_tabs, inputs=[state_empty], outputs=[state_empty, *ui.pages], show_progress=False)

    def refresh():

        for pg in ui.stored_extra_pages: