Found at http://askubuntu.com/questions/230300/incorrect-work-gnome-terminal

echo -e 'foobar\e[3Dquux'
echo -e 'foobar\e[3;Dquux'

xterm: Both do the same: print "fooquux" (the cursor is moved back by 3 by the escape sequence).

vte: The first one works, the second one prints garbage (unrecognized escape sequence).

Similarly, the "clear" command emits \e[3;J with a superfluous semicolon. We protect against this in caps.c by catching %mJ instead of %dJ. Apparently we need a more generic solution for this.