Title says it all. My KDE file picker used to show the thumbnails but after upgrade to KDE Neon 5.21.4 it only shows the file type icon. How can I get my pictures back?

The first image is the file picker with the file icons instead of the tile thumbnails. Below is a screenshot of Dolphin showing how the file picker was and how I want it to be.





This had an obvious answer. I can't see how to delete my stupid question: