For whatever it is worth, I was able to find a work around on Ubuntu 20.04 using the prepackaged Sage 9.0. The trick is to follow the advice on issue 52 by editing the line exec sage-ipython "$@" -i in /usr/bin/sage and changing it to exec sage-ipython "$@" --simple-prompt -i . It is also necessary to add (setq sage-shell::sage-simple-prompt nil) to the .emacs file. All this was found to work with the latest sage-shell-mode version from its git repository that had Emmanuel Charpentier's patches merged in.