Comparison between SN 2019jrj spectra and other GRB SNe. (a) Spectra of SN 2019jrj at maximum light obtained under the assumptions of a jet break at 7 rest-frame days (grey upper curve) or no break (black lower curve) and corrected for Galactic reddening (E(B − V)_Gal ≈ 0.013 mag; Schlafly & Finkbeiner 2011) and line-of-sight reddening at the source (E(B − V) = 0.3 mag). For comparison, maximum-light spectra of the GRB SNe 1998bw (Patat et al. 2001) and 2013dx (D’Elia et al. 2015; Mazzali et al. 2021) are shown. These are de-reddened for Galactic extinction, reduced to the rest frame, and scaled in flux to match the SN 2019jrj flux level. (b) Same as in panel a, but compared with maximum-light spectra of the core-collapse Type Ic SNe 2004aw (Taubenberger et al. 2006) and 2006aj (associated with an X-ray flash; Pian et al. 2006; Mazzali et al. 2006). (c) Same as in panel a, but compared with maximum-light spectra of the core-collapse Type Ic SNe 1994I (Filippenko et al. 1995; Foley et al. 2003) and 2002ap (Mazzali et al. 2002; Foley et al. 2003).