Plots cannot be combined individually

[nmueller18]

Currently, it is possible to show individual plots without prompt by, e. g., plot(lifetable, display = "dx"). However, it is not possible to combine individual plots, e. g. by ggpubr::ggarrange(plot(lifetable, display = "dx"), plot(lifetable, display = "lx"), ncol = 2. This throws the error Cannot convert object of class list into a grob. Likewise, pl <- plot(lifetable, display = "dx") does not save a grob-object for later use but a list with the sole entry "ask - FALSE".