You want to boost this toot:
oh ! This is dolphin ! Sorry about that. I need more sleep. It looked like Gnome-file using a bad GtkTheme with an unsupported dark mode enabled. I was of my rocker.
A while ago I got that exact same result in KDE switching from a dark color-theme to a light color-theme... Just closing then opening it again solved it... But it's been a while this was fixed... But It's still a present bug on my Debian home server (I put a kde desktop on it... since I like to host game servers on it and most of them requires a damn UI to work well... Like "space Engineers".). But any "up to date" distro should not have this bug... hm...
A while ago I got that exact same result in KDE switching from a dark color-theme to a light color-theme... Just closing then opening it again solved it... But it's been a while this was fixed... But It's still a present bug on my Debian home server (I put a kde desktop on it... since I like to host game servers on it and most of them requires a damn UI to work well... Like "space Engineers".). But any "up to date" distro should not have this bug... hm...