This is undoubtedly the most ugly program in the distribution. It was one of the first “serious” programs ported, and still has a lot of historical baggage. Ideally, there would be a general tty widget and then vt102 and tek4014 subwidgets so that they could be used in other programs. We are trying to clean things up as we go, but there is still a lot of work to do.
Reminds me of the xterm(1) README: