micwoj92 [1] filed a deletion request for seaside [2]: There is post on website from October 1, 2018 saying that the development has shifted to GitHub, but seems that the one click experience installer used in this PKGBUILD is no longer updated http://seaside.st/download/pharo#16819391 , also orphaned
[1] https://aur.archlinux.org/account/micwoj92/ [2] https://aur.archlinux.org/pkgbase/seaside/