Action button as accordion panel icon ruins accordion

When adding an action button as the icon for an accordion panel, the accordion fails to render correctly. The first title is shown below the panel, and the rest of the panel do not appear at all.

Example app:

from shiny import App, Inputs, Outputs, Session, reactive, render, ui


def make_items():
    return [
        ui.accordion_panel(
            f'Section {letter}',
            f"Some narrative for section {letter}",
            icon=ui.input_action_button(id=letter, label='#'))
        for letter in "ABCDE"
    ]


app_ui = ui.page_fluid(
    ui.accordion(*make_items(), id="acc")
)


app = App(app_ui, None)

Thanks for producing this package, I'm really enjoying using it.

Start by running the provided Python example app and inspect how ui.accordion_panel renders an ui.input_action_button used as its icon. Trace the accordion and action-button rendering paths to find why the first title is misplaced and later panels disappear; done means all five panels render correctly with the action-button icons.