Install libayatana-indicator3-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libayatana-indicator3-dev
Description:
panel indicator applet - library development files (GTK-3+)
The Ayatana Indicators library contains information to build indicators to go into modern desktops' indicator applets. . This package contains files that are needed to build GTK-3+ applications with Ayatana Indicator support.
Homepage: https://github.com/AyatanaIndicators/libayatana-indicator
Version: 0.6.2-1
Section: universe/libdevel