Metallicity comparisons for stars that are added by our new relaxed filters. The text in the figure describes stars newly added in each step. For example, stars in the top panels satisfy all the conditions in the MP-filters except for flags_gspspec[0-6] ≤ 1. We refer the readers to Sect. 4.2 for more details. We use larger symbol sizes for stars that have [Fe/H] < −1.5 in one of the two metallicities being compared. The gray lines show Δ[Fe/H] = 0 and ±0.5 dex. We show median metallicity uncertainties for GSP-Spec and our measurements as vertical lines for stars with [Fe/H] < −1.5 on the left and for all the stars on the right.