Galaxies per absorption system. Left: Distribution of the number of galaxies that are within ±500 km s⁻¹ of strong ($W_{\mathrm{r}}^{2796}>0.5$ Å) absorption systems, within the MUSE FOV, and within the MUSE wavelength coverage for [O II] emitters, i.e. 0.35 < z_abs < 1.45. The mean (median) number of galaxies is 2.9 ± 1.6 (3.0), respectively. Right: Red (hashed) histogram shows the number of galaxies around strong ($W_{\mathrm{r}}^{2796}>0.5$ Å) Mg II absorption systems within 100 kpc in the redshift range 0.35 < z < 1.45 suitable for [O II] emitters, from the DR2 (DR1) samples, respectively.