Install sni-qt by entering the following commands in the terminal:
sudo apt update sudo apt install sni-qt
Description:
indicator support for Qt
This plugin provides indicator support for Qt. It allows applications to export their systray transparently to the indicator system.
Homepage: https://launchpad.net/sni-qt
Version: 0.2.7+17.04.20170112-0ubuntu1
Section: universe/x11