Yes, I tested it. Before displaying the Save As dialog for naming your new file a write to the original takes place. They probably just do a copy and rename fi

Yes, I tested it. Before displaying the Save As dialog for naming your new file a write to the original takes place. They probably just do a copy and rename file operation afterwards. Interesting fact: if you abort the Save As dialog and try to close the original they ask you to "Revert Changes".