r-band magnitude as a function of the absolute value of the redshift, colour-coded by the survey that provided the redshift measurement (see N_{lead, X − ray} in Table 1). The upper histogram shows the redshift distribution with regard to the number of counts divided by the eFEDS area (140 deg² as in the green contour of Fig. 1, Brunner et al. 2022), while the histogram on the right displays the number of counts for r-band distribution. The absolute value of the redshift is plotted to allow the display of Galactic objects (|z|≲10⁻³) with negative radial velocities.