How to finish installing Gnome on Gentoo?

Question

Gentoo

I'm stuck on installing Gnome, I use the recommended USE flags, but for some reason the OS ignores them, help with advice to get the ball rolling.

marley / # emerge --ask --newuse gnome-base/gnome
setlocale: unsupported locale setting
setlocale: unsupported locale setting

 * IMPORTANT: 12 news items need reading for repository 'gentoo'.
 * Use eselect news read to view new items.


 * IMPORTANT: 2 config files in '/etc/portage' need updating.
 * See the CONFIGURATION FILES and CONFIGURATION FILES UPDATE TOOLS
 * sections of the emerge man page to learn how to update config files.

These are the packages that would be merged, in order:

Calculating dependencies... done!

!!! The ebuild selected to satisfy ">=media-libs/libmediaart-1.9.1:2.0[introspection]" has unmet requirements.
- media-libs/libmediaart-1.9.4::gentoo USE="gtk introspection qt5 -test -vala" ABI_X86="(64)"

  The following REQUIRED_USE flag constraints are unsatisfied:
    at-most-one-of ( gtk qt5 )

  The above constraints are a subset of the following complete expression:
    at-most-one-of ( gtk qt5 ) vala? ( introspection )

(dependency required by "media-sound/gnome-music-3.24.2::gentoo" [ebuild])
(dependency required by "gnome-base/gnome-extra-apps-3.24.2::gentoo[tracker]" [ebuild])
(dependency required by "gnome-base/gnome-3.24.2::gentoo[extras]" [ebuild])
(dependency required by "gnome-base/gnome" [argument])

In the /etc/portage/make.conf file, the appropriate USE flags are set.

Answer 1

at-most-one-of ( gtk qt5 )

One of...