Nebular spectra of SN 2020jfv compared with the normal SN 2020jfo, the CSM interacting SN 2020amv, and the transitional SN 2019oys (Sollerman et al. 2020). Right panel: zoom-in on the Hα line profile in velocity space. Hα dominates all these spectra, but the spectral evidence for CSM interaction is more subtle in SN 2020jfv, with a small structure visible at the red end of the line in the high-S/N Keck spectrum. The peak of this line is affected by a cosmic-ray hit and is therefore not shown.