Stellar effective (half-light) radius in F444W as a function of the stellar mass. Filled stars show CO emitters identified by color as indicated in the legend. Filled diamonds show a variety of sources at 2 < z < 3 (lilac: ALMA-selected galaxies from Boogaard et al. 2024; pink: SMGs in the SMACS J0723−7327 field from Cheng et al. 2022; sea green: some of the SMGs in PEARLS from Cheng et al. 2023; orange: HST-dark galaxies from Nelson et al. 2023; and brown: SMGs in the Abell 2744 field from Price et al. 2023). The magenta line shows the average relation derived for a sample of SFGs at z = 2.5 by Ward et al. (2024).