Problem with ACR-Filter in Photoshop

I've recently upgraded to the newest version of Photoshop and ACR on my iMac (Catalina 10.15.5 - dark mode). When I open an image in Photshop and use the ACR-Filter on it, the contents of the ACR-Popup become unreadable. The background of the window is black and there is no description on the sliders and tools. Has someone encountered the same problem? Does anyone know a solution?