KDE: update icon thinks I have a light plasma theme - eviltoast

Since I upgraded all my devices to KDE 6 I have this weird issue with my laptop and media PC. The software update icon that sits in the tray and starts Discover seems to think I’m using a light plasma theme. It’s only this one icon, and it’s the same for all icon themes. I do not have this issue on my desktop, which has the same updates (comparison in screenshot).

I have tried the following to no avail:

  • switching between multiple icon themes
  • switching between KDE light and dark plasma themes
  • deleting ~/.share/icon-cache.kcache

Anyone have any further ideas?

OS: Nobara release 39 (Thirty Nine) x86_64
Kernel: 6.7.6-201.fsync.fc39.x86_64
Shell: bash 5.2.26
Resolution: 2560x1440
DE: Plasma 6.0.1
WM: kwin
Theme: [Plasma], Breeze [GTK2/3]
Icons: Papirus [Plasma], Papirus [GTK2/3]