Awesome. Thanks!
Understood about overwriting the plots, although I'm not actually clear that it could be assumed that might not be a desired behavior in some cases.
Even if that can be assumed, I don't know why it would preclude a save.
My usual attention is to that * in the filename to confirm a save (i.e., munging.Rmd* -> munging.Rmd).
For that to clear, when it fact it failed to save, is troubling to me.