Selection function for the sources selected to be part of GS/E, described by the sources with RVs, ϖ > 0.1 mas, ϖ/σ_ϖ > 5 mas, and −1500 < L_z < 150 kpc km s⁻¹, with respect to Gaia DR2 and DR3 in the top and bottom panels, respectively. The top panel belongs to the original sample in Gaia DR2 described by Helmi et al. (2018), while the bottom panel shows the same cuts applied to Gaia DR3. The maps correspond to the resolution of HEALPix level 4. The magnitude and colour dependencies have been marginalised out.