Unlike other pseudo-encodings these don't break gtk-vnc
because older versions don't suport the extended desktop
resize extension in the first place.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20210125104041.495274-3-kraxel@redhat.com>