[Bug] Package list etc. missing when toggled via taskbar

[Dasug]

When I open the widget by clicking the icon in the taskbar, the entire main area showing the out of date packages / the first setup / the news etc. are all missing:

If instead I place the widget somewhere on the desktop as a floating widget, is displays perfectly fine:

I'm using KDE Plasma 6.0.4 and installed the widget from the KDE store.

(Also the "Update your system" icon is missing but that's probably unrelated and just the fault of my KDE icon theme.)