Planet radius of warm (left of the vertical line) and hot giants (right of the line) as a function of incident stellar flux. The stellar metallicity is colour-coded, while the size of the dots tracks their planetary masses. The dashed line is the radius of a 4.5 Gyr old, 1 M_J, pure H/He planet (with no metals), without additional internal heating. Figure adapted from Thorngren (2024). Only planets with masses above 0.1 M_J are shown.