Mass-metallicity relation for the Alessi et al. (2020, APC) population of warm Jupiters, compared to the hot Jupiter population from Paper I (faded points). The Solar System giants (inferred by methane abundance and taken from Kreidberg et al. 2014), WASP-43 b (Kreidberg et al. 2014), GJ 436 b (Morley et al. 2017), and HAT-P-26 b (MacDonald & Madhusudhan 2019) (inferred from their water abundance) are also shown. In addition, we include the recent O/H measurement for Jupiter by Li et al. (2020) to show that, within uncertainty, the relation is independent of whether we used C/H or O/H to determine the metallicity. We include the O/Hs for our synthetic population and find that they follow the relation up to a mass of a few Jupiter masses, where they appear to flatten out. The colour of each point denotes the trap from which the planet originated: ice line (blue), dead zone (orange), and heat transition (green). This is a recreation of Fig. 12a from Paper I.