I thought I made so many tweaks and hacks it came from them but seems no. That said, I don't figure what's in common between blue theme and dark minimal one No pb after logoff or reboot, window color setting apply nicely in winrar and active disk image What I 've done: I exported in hackfile the fonts and system metrics from your thin line theme and merged it on DMG and hurray ! Save and copy the updated style in resources without using WSB to use it directly The window color applied correctly under 'thin line' theme and some other ones. It also occured with your blue theme ( winrar and active disk image app, same grey although window already set to dark in WSB ), it worked ONLY when testing Nintendo Epic PlayStation 5 XBOX Series Rockstar Games Mog Station Bethesda. I then tried search under other themes if same and I found that : Tried on a clean system but the same grey window under DMG Thanks for helping but I've already tried it without success as it came back after logoff or reboot even when saving under WSB ,BUT interesting following notes how I solved this issue ( weird if it concerns DMG releases but nobody yet report similar things ) : Hi my friend ! didn't want to bother you on VC I 'temi grafici' di WinRAR cambiano tutte le icone e le immagini del programma secondo un nuovo stile grafico.