Bitcoin Core's gui is pretty broken for a someone using macOS in "Dark
Mode"; the biggest issue being lots of white text on a white background,
leaving most inputs, the rpc console etc unusable.

This is likely something we'll have to wait for Qt to fix/support, so
it's probably easiest to just disable for now, rather than provide a
broken UI; see screenshots below. This issue might not have come up much
yet, given the issues with the 0.17.0 dmg.