Positively biased UI (Bright/Light Theme)

[BoEsse]

Hello XDM community!
I just installed XDM and was greeted by an eye-shattering dark theme. Ususally, apps respect the OS setting, but that's ok sigh.
But even after going through the settings and reading the docs, I couldn't find where to change it to a positively biased UI.
Only a mysterious setting: Use dark theme if possible (?!)

I am trying 8.0.29 BETA