Similar issue to 6637 where old versions of ggplot object does not display correctly.

Please add an item to the ggplot objects with the version of ggplot2 that created them than can be queried by the user. This way, I can alert the user that the saved ggplot object may have to regenerated.

The issue is that the code that generated the data used for the object is long running MCMC program that saves the output to a directory for later usage. These include basic ggplot plots saved for the user to annotate when the program is done using quarto etc.

If the version is saved with the the ggplot object, I can query the plot object and warn the user if a breaking change has occurred.

Thanks
Carl Schwarz
cschwarz.stat.sfu.ca@gmail.com