[Unit]
Description=Show desktop for a few seconds

[Service]  
Type=oneshot
Environment=DISPLAY=:0.0
Environment=XAUTHORITY=/home/odoo/.Xauthority
ExecStart=/usr/bin/nitrogen --set-zoom-fill --random /home/odoo/wallpapers/
ExecStart=sh -c "xdotool key Super_L+F2; sleep 7; xdotool key Super_L+F1"
User=odoo
Group=users