Changing to Slackware 11, I found that the key sequence for
undoing change. While before I just typed ^_, now I have to
have the Shift key pressed too.
While the man page for Joe suggests this is a keyboard issue,
the kbd is the same as before. So I suspect this to be a
config thing, either in xterm, X11 (xorg 6.9), or Joe.
I couldn't find where though.
Suggestions would be appreciated.
Your xterm-resource file /etc/X11/app-defaults/XTerm (the path may be different in different distro) must have correct description for this key in section *VT100.Translations. For example:
*VT100.Translations: #override \
Ctrl<Key>minus: string("\037") \n\