Install libfltk-gl1.3 by entering the following commands in the terminal:
sudo apt update sudo apt install libfltk-gl1.3
Description:
Fast Light Toolkit - OpenGL rendering support
This package contains the files necessary for running programs dynamically linked with FLTK's OpenGL rendering bindings. . The Fast Light Toolkit (FLTK) is a cross-platform graphical user interface toolkit originally based on libForms.
Homepage: http://www.fltk.org/
Version: 1.3.4-6
Section: universe/libs