Since there are quite few appealing dark themes for OMV, I had sat down yesterday and put together a Dark Blue.
The whole thing is available for download on GitHub. Who finds errors ... can keep them Just kidding. Of course feedback is desired. This is tested for OMV5.
For older versions there may be differences in the class. So just test
Now have fun with the Dark Blue. Regards
(Edit 22.10) ... und für unsere deutschen Zuschauer hier die Anleitung.