Redshift distribution of MUSE sources at z = 0.9 − 2.5 in bins of Δz = 0.01 (gray histogram). The six MUSE sources (m1 − m6) in the z = 1.69 overdensity are shown in light green. The red curve shows the expected background curve, obtained by smoothing the MUSE redshift distribution, used to quantify the significance of the redshift structure. The two additional sources at z = 1.69 found by LUCI (including the FRII host) are shown in yellow.