R version 4.0.0 has been released today. In the case of complex ggplots there is a noticeable improvement in performance. As is normal in CRAN, packages are automatically tested. Most of the packages I have developed are in CRAN, and you can easily see their check status at any time in the page where they are listed. At the moment there are warnings under OS-X affecting the building of vignettes for many different packages in addition to several of my own, all with the same message. I suspect this problem is related to ‘knitr’ or ‘roxygen2’.