If a file has no extension and "unknown" mimetype in header : Thunar shows no icon.
Could it be that your GTK+ (perhaps the theme as well) is broken and the GTK_STOCK_FILE icon is not available?
Created attachment 3365 screenshot
(In reply to comment #1) > Could it be that your GTK+ (perhaps the theme as well) is broken and the > GTK_STOCK_FILE icon is not available? Yes, indeed, I happily change the bug as invalid : adding the "gtk-file" icon to the theme fixes the problem. Thank you :) JP