I don’t know if it’s a glitch or if it was intentional but now when you retrieve content info, the thumbnail (when in thumbnail view) doesn’t get updated. The only way I have found to have the thumbnail appear is to eject the USB drive and then plug it back in. In the previous firmware, after having retrieved the content info the thumbnail was immediately updated.
Maybe you should try contacting WD’s Technical Support about this. You can do so either by phone or email.
To Contact WD for Technical Support