Log(Cl²⁺/O²⁺) as function of ionisation degree, O²⁺/O, for H II regions (blue circles) and SFGs (black squares) of our DESIRED-E sample. The dashed black line and the grey band show the Solar System log(Cl/O) and its associated uncertainty obtained from the Solar System Cl/H ratio recommended by Lodders & Fegley (2023) and solar O/H ratio proposed by Asplund et al. (2021). The different curves represent the ICF schemes used in this study: Amayo et al. (2021, dashed-dotted red lines) and Izotov et al. (2006, dotted lines with colours corresponding to three metallicity ranges).