Is there somewhere an embedded Save document preference that I can click off? I can’t make changes to a file, hold down the Option key, select SaveAs, name the new file differently and keep the original file unchanged. Revert to Last Saved Version doesn’t do it either and changing the setting in the General Preference of System Preferences to “Ask to keep changes …” only works if you do not wish to Save any changes. The only way I can do so is to work on a duplicate of the file.