Folder art suddenly gone

[Linthorn]

I have a fairly large collection and suddenly MM is not showing the folder art in the browser window. It shows everything with a folder icon, but no art. I looked and each folder has an art file (folder.jpg, cover.jpg, etc) and it shows art for individual tracks. Up until recently, it always showed the art. I have rebooted, rescanned, and even added new material. Is there a setting that got messed up? Really would like to have the cover art back.

[Lowlander]

What Media Tree node are you browsing in and is this an issue for Album folders or folders with a mix of files?

[Linthorn]

I'm looking in the Folders node. Album folders. Don't really have much as far as mixes. I can see folders for albums, and those folders usually have an art jpg in them, as well as having one in the tag. I can see cover art in the library nodes. But the folder node just shows grey folder icons. Didn't use to be this way, so something changed.