sudo apt purge e3
sudo update-alternatives --install /usr/bin/e3 e3 /usr/bin/geany 1
sudo update-alternatives --install /usr/bin/gedit gedit /usr/bin/geany 1
With e3 removed, when I retried prior to running update-alternitives, roxterm errdialog stated
"Unable to find a text editor. Please install gedit, kvim, kate or emacs"
so the 3rd command, above, is just to preclude similar surprises in case some app contains a hardcoded call to gedit.
edited to add:
across 3 tests, each aborted using killall, the"hangs" spammed 286 megabytes (endless ESC sequences) into ~/.desktop-session/log