Top panel: Average void size functions, per degree squared, of 2D WL voids from 256 light-cone random realizations with redshift z_s = 1, for the different analyzed models: ΛCDM (black), fR4 (green), fR5 (blue), fR6 (red), and ΛCDM_0.15 eV (purple). Bottom panel: Corresponding residuals computed with respect to the ΛCDM model. In both panels, the shaded regions of the same colors around the curves indicate errors, computed as the standard deviation of counts in each bin divided by the number of maps.