All apps by default and for compatibility reasons render their windows in light mode, but I just couldn't get over having Oolite with a blazing white title bar sitting in the middle of my screen while the rest of my desktop was nice and dark, so I thought I'd better do something about it and the result is quite nice, if I may say so. A pull request is being prepared, but in the meantime, for those who use dark mode, play in a window often and would rather take care of their eyesight, the auto-build artifact generated from github can be downloaded from here: https://drive.google.com/file/d/1MJJaGu ... sp=sharing

If your system is in light mode, then of course everything will look as it always has. There should be no visible change there, since Oolite has always rendered in light mode till now.
The feature is Windows-only at this time. Please check and let me know if you discover something amiss. This will probably be merged into master after phkb's galactic hyperspace stuff.