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Translations:GNOME/Guide/12/en
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Before installing GNOME, editing the system's USE variables is a good idea. Make sure that X, gtk, and gnome are in the USE variable located in /etc/portage/make.conf. It is recommended to enable support for D-Bus system-wide. Systemd includes this system message bus. Add systemd to the USE variable as well (D-Bus is a system message bus that GNOME uses extensively). If no KDE support is required, remove qt4, qt5 and kde from USE. USE flags can be removed by adding a minus sign (-) in front of them. See the example below for the minus sign used properly.