Magnitude difference m_A − m_B vs. λ₀ between images A and B. The red squares show the integrated continuum and the black circles the emission line core without the continuum using X-shooter. Shown are the measurements obtained from the literature: HST (Shajib et al. 2019) (magenta triangles), VISTA (Lee 2019) (cyan diamonds), DES (Agnello et al. 2018) (blue diamonds) and HST F105W/G102 (Nierenberg et al. 2020) (orange square for continuum and orange triangle for a narrow emission line). The red line is the median of the continuum, the dotted red line the standard deviation, the black line the emission line core, and the blue line the literature.