On Ubuntu 20.04 running X11, there is this message on every Blender startup:
Unable to find 'wl_proxy_marshal_flags' in 'libwayland-client.so.0'.

The reason is that we build against Wayland protocols 1.21, which in turns requires
Wayland on the distribution to be 1.21+, which is not the case on Ubuntu 20.04.

This simply silences the warning. An improvement would be to explain the user that
their Wayland version is too old when neither X11 or Wayland can be found. Though
that's not trivial and a situation with old Wayland and no XWayland seems unlikely
to happen in practice, so I did not bother.