Hi - I’ve not seen anything about this issue except where it pertains to KDE, so I hope you don’t mind me posting.
I am using a dark theme in XFCE - Zukitre-dark - and in recent weeks I’ve found that Pamac is not fully following it. In particular, the background for application entries through the main interface is not switching to compensate, and clashes with the font as a result. I’ve tried reinstalling the application but it hasn’t made any difference. It works if I switch away from a dark theme, but I don’t particuarly like them and have not found a problem with any other application. It means I sort of have to squint when installing software. Can anyone help?
There is so many themes created over the years for the various toolkit versions.
And not all of them are actively maintained - so installing a theme - one can expect small issues.
It is also known that some theme can make the system go haywire - mostly seen with Plasma and Gnome. Also known that a small number of applications can go haywire if the theme is poorly constructed or unmaintained.
And theming is maintained as many different locations and config files. Finding those small annoyances can be a hairpulling experience.