Extinction estimates of high Galactic latitude stars with |b| > 50° and parallax uncertainty better than 20% before applying the filters of Eqs. (8)–(10). Panel a: distribution of A_G values (black), and distribution of simulation results with PARSEC photometry for A₀ = 0 and [Fe/H] = 0 (orange). Panel b: density of sources in colour–extinction space showing two sets of outliers with unexpectedly large A_G estimates at G_BP− G_RP ≃ 1 mag and ≃2.3 mag. Panel c: colour–magnitude diagram highlighting the location of these two sets of outliers.