Comment 3 for bug 1769775

Downstream report: https://bugs.launchpad.net/ubuntu/+source/xfce4-pulseaudio-plugin/+bug/1769775

To reproduce:

1. Add more than one xfce4-pulseaudio-plugin to the panel. (For example, because you have a panel on more than one monitors and a plugin on every panel.)
2. Adjust the volume.

Result:

You get a bubble for every instance of the plugin. If you have three plugins, the volume notification will be displayed three times.

See screenshot.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xfce4-pulseaudio-plugin 0.4.1-0ubuntu1
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: XFCE
Date: Tue May 8 00:55:38 2018
InstallationDate: Installed on 2018-05-07 (0 days ago)
InstallationMedia: Xubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
SourcePackage: xfce4-pulseaudio-plugin
UpgradeStatus: No upgrade log present (probably fresh install)