File-visiting buffers are by default saved at certain points in time.
This doesn’t guarantee that Magit buffers are always up-to-date, but,
provided one only edits files by editing them in Emacs and uses only
Magit to interact with Git, one can be fairly confident. When in
doubt or after outside changes, type g (magit-refresh) to save and
refresh explicitly.
This option controls whether file-visiting buffers are saved before certain events.
If this is non-nil then all modified file-visiting buffers belonging
to the current repository may be saved before running commands,
before creating new Magit buffers, and before explicitly refreshing
such buffers. If this is dontask then this is done without user
intervention. If it is t then the user has to confirm each save.