In Tools>Options>File List, I can choose to Show thumbnails in folders, which displays four tiny, arbitrarily-selected thumbnails of a folder's contents on the folder icon in the File List pane.
How about this alternative, as in Windows Vista: let me right-click the folder’s icon and choose a single image from the folder or its subfolders to place in the icon. This could be a much more meaningful reminder of what's in the folder.


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