[arch-general] libxfont: removing fontsproto breaks dependency 'fontsproto>=2.1.3'

[Eduardo Machado]

2018-02-10 1:55 GMT-02:00 Doug Newgard via arch-general <
arch-general at archlinux.org>:

> Not gremlins, just an old package that never got cleaned out. Pacman
> doesn't do
> this automatically.
>

Sorry to hijack this trhead,

but so that pacman does not clean automagically this kind of packages. What
is the recommended way to keep a clean box?