I use #000000 as my background. Both my Window and View background are set to #000. Most stuff, if not everything, is as dark as possible with Purple as the accent colour for stuff like selections and progress bars. Unfortunately…
This only happens in the settings window or also in any listview? Could you check view>alternate?
Can’t really reproduce the issue. That’s plasma 6?
KDE Plasma 6.1.4, from what I can tell.
You can see here Almost illegible text in some (Gtk?) apps - #6 by akselmo *not just gtk apps
Hmm… bug report says resolved upstream but it’s still happening.