Install libgtk2-ex-volumebutton-perl by entering the following commands in the terminal:
sudo apt update sudo apt install libgtk2-ex-volumebutton-perl
Description:
Gtk2 widget to control volume and similar values
Gtk2::Ex::VolumeButton is a simple Gtk2 widget based on Gtk2::ToggleButton to control the volume and similar values. It consists of a Gtk2::ToggleButton widget displaying an image representing the current volume. When the button is clicked a popup window containing a Gtk2::VScale widget shows up and allows you to change the widgets volume value. It's also possible to change the volume using the scroll wheel over the toggle button even if the popup window isn't shown. . This widget is modeled after the widgets use in gnome-panel, muine and rhythmbox. Much code is stolen from the muine volume-button widget.
Homepage: http://search.cpan.org/dist/Gtk2-Ex-VolumeButton/
Version: 0.07-2
Section: universe/perl