Metallicity gradients for the main sources in A2744-YD4 (top two rows), BDF-3299 (mid-bottom), and COSMOS24108 (bottom). Radial annuli have radial width of 1 spaxel (0.05″). The wavelength-dependent spatially smoothed cube was used (details in Sect. 2.2). Metallicity gradients (right) and [O III] maps (left; also from smoothed cube), where the concentric annuli are reported on the source (the shaded region in the COSMOS24108 map was masked out from the gradient; see text). The vertical grey dashed line marks the spatial resolution (σ_res.). The fluxes of emission lines far in wavelength are corrected for extinction based on Hγ/Hβ in A2744-YD4 and BDF-3299, while in COSMOS24108 Hα/Hβ is used for that and also [S II] and Hα are used to infer the metallicity. A cut of S/N > 3 on the peak flux of each line is applied.