Function theme_sub_plot 

pub fn theme_sub_plot(
    title: Option<ElementText>,
    subtitle: Option<ElementText>,
    caption: Option<ElementText>,
    background: Option<ElementRect>,
    margin: Option<Margin>,
) -> ThemeUpdate

ggplot2 4.0’s theme_sub_plot(title =, subtitle =, caption =, background =, margin =) (#413).