notification-daemon при запуске (systemd) не находит дисплей:
notification-da[825]: cannot open display: :0$ cat ~/.config/systemd/user/notification-daemon.conf
[Unit]
After=at-spi-dbus-bus.service
Requires=at-spi-dbus-bus.service
After=gvfs-daemon.service
Requires=gvfs-daemon.service
After=dbus.service
Requires=dbus.service
Description=Notification Daemon
[Service]
Type=dbus
EnvironmentFile=-/etc/locale.conf
Environment=DISPLAY=:0
BusName=org.freedesktop.Notifications
ExecStart=/usr/lib/notification-daemon/notification-daemon
[Install]
WantedBy=default.target