Getting rid of warning messages when using ggplot2 and ggfortify R packages

library(ggplot2)
library(ggfortify)
First example in help("lm")
Annette Dobson (1990) "An Introduction to Generalized Linear Models".
Page 9: Plant Weight Data.
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I think the easy first-step is to suppress it using suppressWarnings(). However, this can be nuclear at times, and completely mask other warnings that may otherwise be informative/useful.

I suggest going one step further and only suppress those warnings. This can be done using withCallingHandlers (a sibling of tryCatch) and invokeRestart("muffleWarning").

suppressWarnings_ggfortify