BTA/SCORPIO-II spectrum of the optical afterglow of GRB 220107A obtained 1.36 days post-burst. Top panel: Two-dimensional spectrum showing the trace of the GRB afterglow (upper) and an unrelated foreground galaxy at z = 0.309 (lower, Pankov et al. 2022; Castro-Tirado et al. 2022). Bottom panel: Flux-calibrated one-dimensional spectrum smoothed with a 4 × 4 pixel median filter. Prominent absorption features, including Fe II, Mn II, and the Mg II doublet, are marked. All identified lines are consistent with a common absorption system at z = 1.246, which we consider as the redshift of the GRB.