Binary package “libgxwmm-dev” in ubuntu focal

Guitarix - GTK+ C++ widget library (development files)

 Guitarix is a rock guitar amplifier for the JACK Audio Connection Kit with
 one input and two outputs. It is designed to produce nice
 trash/metal/rock/blues guitar sounds.
 .
 Guitarix is available as a GTK+ interface and the project provides LV2 and
 LADSPA plugins (see the guitarix-lv2 and guitarix-ladspa packages).
 .
 This package contains development files for Guitarix's GTK+ C++ widget library.