Effective temperature at a Rosseland optical depth of 2/3 as a function of the transformed mass-loss rate Ṁ_t for the whole set of models from Sander & Vink (2020). For log (Ṁ_t [M_⊙ yr⁻¹]) < −5.5, T_2/3 is effectively independent of Ṁ_t. In Sander & Vink (2020), the value of T_* is fixed for all models, but the difference in L/M still yields a wide range of T_2/з values. The dashed-dotted line represents a linear fit of the temperature trend for log (Ṁ_t [M_⊙ yr⁻¹]) > −4.5 while the dotted curve represents the fit for the new model sequence illustrated in Fig. 11.