Install libqt4-help by entering the following commands in the terminal:
sudo apt update sudo apt install libqt4-help
Description:
Qt 4 help module
Qt is a cross-platform C++ application framework. Qt's primary feature is its rich set of widgets that provide standard GUI functionality. . The QtHelp module provides classes for integrating online documentation in applications.
Homepage: http://qt-project.org/
Version: 4:4.8.7+dfsg-7ubuntu1
Section: universe/libs