title_body: Is it possible to set Calibre Editor to automatically backup a book file before modifying it? Pretty much as the title says, is it possible to set Calibre to automatically create a backup copy of a given .epub file before editing it?
  
  When experimenting, it would be handy to keep the original file untouched.
upvoted_answer: I've contacted Calibre's developer, he said that it is not possible and that he doesn't find such feature useful, so he is not willing to implement it.