Upper panel: Surface abundances by mass fraction X (relative to solar abundances) of our models with significant neutron-capture nucleosynthesis compared to observations of the helium-rich hot-subdwarf stars LS IV −14 116 (Dorsch et al. 2020), EC 22536−5304 (Dorsch et al. 2021), Feige 46 (Latour et al. 2019), HZ 44, and HD127493 (Dorsch et al. 2019). Lower panel: Same as the upper panel by showing the abundances relative to iron, which form the main nuclei seed of the synthesized heavy elements. The abundances of LS IV −14 116 and EC 22536−5304 include preliminary values obtained from HST far-UV spectra (Dorsch et al. 2022), which will be described in detail in a future paper.