How to disable popup notifications in Xubuntu

The popup notifications in Xubuntu have always annoyed me, they pop up right over top of the window controls and generally just get in the way. It is the xfce4-notifyd service that is responsible. The popup notifications are almost never informative, but some apps depend on the service, so I can't just uninstall it. So I set about finding out how to disable the notifications without actually removing it. It turns out it's fairly simple:

cd /usr/share/dbus-1/services
sudo nano org.xfce.xfce4-notifyd.Notifications.service

Change it to look like this:

[D-BUS Service]
Name=org.freedesktop.Notifications
#Exec=/usr/lib/xfce4/notifyd/xfce4-notifyd
Exec=/bin/true

Now the popups will stop but those apps depending on it (like the volume controls) will still work.