T_dust and ⟨U⟩ as a function of redshift. The blue dots represent the T_dust of this work, the blue line is the best-fit (up to z = 5), the dashed blue line is the best-fit extrapolation (for z ≥ 5), and the blue shaded area represents the 68% uncertainty of the fit. From the literature: S18 (grey solid line), Magnelli et al. (2014) (grey dotted line) and Bouwens et al. (2020) (grey dash-dotted line) converted using Eq. (8). Magdis et al. (2012) (grey, dashed line) and Béthermin et al. (2015) (grey dots) converted using Eq. (9). We also re-fitted the two stacks from Béthermin et al. (2020) (grey dotted error bars) using template library from S18.