NoobAlice [1] filed a deletion request for libxfce4ui-nocsd [2]: With the release of Xfce 4.18, this package is no longer necessary as CSD is now optional. Thank you for maintaining! https://github.com/Xfce-Classic/libxfce4ui-nocsd/issues/15
[1] https://aur.archlinux.org/account/NoobAlice/ [2] https://aur.archlinux.org/pkgbase/libxfce4ui-nocsd/
