Install libdockapp-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libdockapp-dev
Description:
Window Maker Dock App support (development files)
Simple library that eases the creation of Window Maker dock apps. It provides functions that set up a dock app in such a way that they can be properly docked. It also provides some event handlers and makes it very simple to write dockapps. . This package contains the static library and the required headers. Use it to compile programs which use libdockapp.
Homepage: http://windowmaker.org/dockapps/?name=libdockapp
Version: 1:0.7.2-1
Section: universe/libdevel