Depois de tentar algumas abordagens diferentes, consegui que funcionasse com as instruções no webupd8 site; instalando todas as extensões do shell.
sudo add-apt-repository ppa:webupd8team/gnome3
sudo apt-get update
sudo apt-get install gnome-shell-extensions-alternate-tab gnome-shell-extensions-alternative-status-menu gnome-shell-extensions-user-theme gnome-tweak-tool gnome-shell-extensions-workspace-indicator gnome-shell-extensions-apps-menu gnome-shell-extensions-drive-menu gnome-shell-extensions-system-monitor gnome-shell-extensions-places-menu gnome-shell-extensions-dock gnome-shell-extensions-native-window-placement gnome-shell-extensions-gajim gnome-shell-extensions-xrandr-indicator gnome-shell-extensions-windows-navigator gnome-shell-extensions-auto-move-windows