MarsSeed [1] filed a deletion request for threemawebqt-git [2]: Unused, discontinued, unofficial client from 2018. Users should use either the official threema-desktop or the unofficial threema-for-desktop. Both available on AUR.
[1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/threemawebqt-git/
