Wrong base branch. Closed and re-submitted (see comments).
As well as the magit-process buffer (showing the output of the most recent git command), it would be mightily useful if that output was also appended to a magit-process-log buffer, so that we could see things like the commit hash for the stash that we dropped a couple of commands ago, and then realised that we wanted back (for example :)
Branch phil-s/process-log (branched from maint) implements this.
#505 - Added a running log of git command output.
Finally got it right in #516