Observational HRD of Gaia DR3 YSOs (red contours), KYSOs (blue dots and blue contours), and reference sources (grey dots) as described in the caption of Fig. 1. Most of the KYSOs are located above the main sequence, but other parts of the HRD are also covered. The probability distributions of the G_BP − G_RP colour and the G_Abs are shown in Figs. B.1 and B.5. The main parameters of the distributions are listed in Table 1.