Depau [1] filed a deletion request for newadwaita-gtk-theme [2]:
This theme has been superseded by the main of Adwaita shipped with GNOME in the repos. The package can now be removed.
[1] https://aur.archlinux.org/account/Depau/ [2] https://aur.archlinux.org/pkgbase/newadwaita-gtk-theme/
Request #14726 has been accepted by polyzen [1].
aur-requests@lists.archlinux.org