Florian Müllner authored Feb 26, 2019 and Christian Persch committed Feb 26, 2019

As headerbars combine the functionality of titlebar, toolbar and
menubar, they generally replace (not supplement) those elements.

For that reasons, the default-show-menubar setting is ignored when
headerbars are enabled. However despite not having any effect, the
corresponding checkbox is still shown in the preferences. It doesn't
make sense to expose non-working settings, so hide it when headerbars
are used.

#81