I've been sporadically checking this issue across various machines (new and old) to see if it persists everywhere, but I recently switched a box to use the i3 window manager and I noticed I no longer have issues with box drawing characters. I still have XFCE installed and when I switch back, the issue still occurs. I used Terminator to check in both XFCE and i3; no idea what could be the problem then, but I'll try to investigate more when I have more time.
~Connor
