Li abundance trends in evolved stars. Panel a (top): general stellar distributions of the catalogues of Ding et al. (2024, blue) and Gao et al. (2021, red), showing Li abundances as a function of log g. The horizontal line at A(Li)=1.5 serves only as a reference, while the vertical line marks the end of the stellar giant branch at log g = 3.5. Panel b (bottom): Li abundance of Li-rich giant stars, RGB (blue), HB (red), and AGB (green), as a function of metallicity ([Fe/H]) in the range −4.0 to −1.0. While RGB stars are present throughout the metallicity range, HB and AGB stars appear only for [Fe/H] > −2.5.