[Fe II] forest detected in the G395H data over the ∼5000 Å region of GN-9771. We show the fitted [Fe II] spectrum as described in Sect. 3.3 (green), the He I lines (pink), Hγ (blue dot-dashed), the Hβ model (blue dashed), [O III] λλ4960, 5008 (orange dot-dashed), and [O IIIλ4364 (brown). The residuals of the fit as well as the observational uncertainties on the spectrum are shown in the bottom panel.