Although I've used KDE for years, I now use parts of KDE (konsole, dolphin, etc) on an Arch system running i3.

Mostly everything is running the way I want it to, but right now I have a problem with Dolphin.

There is no "arrow" to for expanding a folder. I can actually click where the arrow should be, and it works, but the situation slows me down drastically as the only way I can tell if a folder is expandable is: 1. just try clicking it; or 2. scan across to the column that shows "x items".

Maybe I've done something with icons at some point, but I've tried running qt5ct and everything else I can think of and I'm stuck. Can anybody help?

This is what I see inside dolphin now:

I don't know also how to resolve this error message this forum is giving me when I attach my screenshot, but below is the link: "It was not possible to determine the dimensions of the image."
https://pasteboard.co/I34Iue1.png