Total number of CCEs assuming a power-law luminosity function. The background color map represents the total number of expected CCEs during Flashlights observations in all of the lensed arcs considered in the current work. The red curve corresponds to N_CCE = 20, i.e., the number of events observed in Flashlights. The shaded green region represents the best-fit β value with 1σ range, i.e., β = 2.37±0.21 (see Sect. 4.2 for more details).