There are empty slots in the "Images" playlist (Windows)

The essence of my problem is as follows. Previously, I played Mystic Warriors on MAME and took screenshots there. After passing, I moved the files to another folder, but the entries in the “Images” playlist remained. Although in theory they should not be displayed in the list! I want to find out how to get rid of non-existent lines. It will be better with the selection of most records.

And another question: “Aren’t you going to add thumbnail scanning for Arcade Machine Emulators?”