libwayland-client-extra++0 binary package in Ubuntu Focal amd64

 Wayland is a protocol for a compositor to talk to its clients as well
 as a C library implementation of that protocol. The compositor can be
 a standalone display server running on Linux kernel modesetting and
 evdev input devices, an X application, or a wayland client
 itself. The clients can be traditional applications, X servers
 (rootless or fullscreen) or other display servers.
 .
 This package ships the C++ bindings for the client side libraries of
 the extra Wayland protocols.

Source package