Dynamical mass (M_dyn) vs. L_int diagram adopted from Palau et al. (2024). Blue symbols represent protostars, VeLLOs, and proto-BD candidates with L_int and M_dyn measurements, while the solid line represents the fit to the data. The shaded area corresponds to two (dark) and five times (light) the uncertainty of the fit. The dashed green lines at the bottom left delimit the region consistent with proto-BDs. We represent IRAM 04191 with M_dyn derived in this work, and L_int from Pérez-García et al. (2025).