The latter trick is also present in the VT100: in 80 cols mode the font matrix is stretched from 9×10 to 10×10 by replicating the rightmost pixel, which is only

The latter trick is also present in the VT100: in 80 cols mode the font matrix is stretched from 9×10 to 10×10 by replicating the rightmost pixel, which is only set in horizontals of line-drawing characters (with dot-streching closing any remaining gaps).