Upper panel: comparison of the STIS spectrum of HD 175640 (black line) with a synthetic spectrum (red line) computed with a line list including the new Mn ii lines; lower panel: the same, but the synthetic spectrum is computed with a line list not including the lines given in Table A.1 (available at the CDS). Only the Mn ii lines are indicated with red labels in the plot. The meaning of the labels is the same as in Fig. 1.