Install gir1.2-wnck-1.0 by entering the following commands in the terminal:
sudo apt update sudo apt install gir1.2-wnck-1.0
Description:
GObject introspection data for the WNCK library
A library to use for writing pagers and task lists. This variant of libwnck provides WNCK for GTK-2 based applications. . This package contains introspection data for Window Navigator Construction Kit, a library to interact with window managers. . It can be used by packages using the GIRepository format to generate dynamic bindings.
Homepage: https://developer.gnome.org/libwnck/2.30/
Version: 1:2.30.7-5.1ubuntu1
Section: universe/introspection