MarsSeed [1] filed a deletion request for gstm-gtk2 [2]: Broken since 2019, as per maintainer's comment from that year.
Upstream's newer versions do not support gtk2, only gtk3. AUR has packages for the latest code, and they still work: - gstm - gstm-git [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/gstm-gtk2/
