Effective survey area for the Legacy Surveys DR10 south and DR9 north depending on redshift. At the limiting redshift z_vlim, the faintest considered cluster member galaxy was observed with 10σ confidence in the z band. Details are given in Appendix B. The luminosity of that galaxy is L = 0.2 L_* for the eROMaPPer (eROSITA Matched-filter Probabilistic Percolation cluster finder) runs which used the grz and griz filter bands and L = 0.4L_* for the runs that also included the w1 band. The dashed lines correspond to the full LS footprint while the continuous lines show the area that is reduced to the overlapping region with eRASS1 (see Fig. 2).