Issues using {ggtext}, element_markdown(), element_textbox()

[MokeEire]

I have been having trouble using ggtext functions inside the theme argument to plot_annotation(). In particular, the error only occurs when also using plot_layout(). I am trying to write a multi-line subtitle, using either element_textbox_simple(), element_markdown, str_wrap(), or a combination of the three.

The code looks as follows:

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  # Tried with layout set using design and ncol
  # plot_layout(design = layout)+
  plot_layout(ncol=1)+
  plot_annotation(title = "Some Title",
                  subtitle = "<span>A long subtitle which needs to be on multiple lines, and _ideally_ use markdown syntax too.</span>",
                  caption = "**Source(s)**: Simply using markdown syntax",
                  theme = theme(plot.caption = ggtext::element_markdown(hjust = 0),
                                plot.background = element_rect(fill = my_col_pal[1]),
                                plot.title = element_text(face = "bold",
                                                          lineheight = 1.2),
                                plot.subtitle = ggtext::element_textbox_simple(lineheight = 1.1)))

And the error returned is:

Error in grid.Call(C_convert, x, as.integer(whatfrom), as.integer(whatto), : Viewport has zero dimension(s)

If I remove plot_layout, there is no issue (except that the plot is not laid out how I would like). I can't imagine this is all the information you need to diagnose this issue, please let me know what other info would be needed to figure this out.

[thomasp85]

Does the error disappear if you make the plot larger? it seems that maybe there's not enough space for gridtext to do its thing?