Gaia EDR3 colour-reduced proper motion diagram for the hot subluminous star region. The grey dots show the objects outside the Magellanic Clouds that conform with all quality criteria. The colour scale shows the number density of Proper Motion Selection 1 and 2 objects in colour-Ho space. The red line shows the cutoff used to remove the main sequence region. The blue line shows the cutoff used to remove the white dwarf region.