Install libqt5websockets5-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libqt5websockets5-dev
Description:
Qt 5 Web Sockets module - development files
Qt is a cross-platform C++ application framework. Qt's primary feature is its rich set of widgets that provide standard GUI functionality. . This package contains the development files needed to build Qt applications using Qt 5 Web Sockets library.
Homepage: https://qt.io/
Version: 5.9.5-0ubuntu1
Section: universe/libdevel