There are two different types of lists in the service structure: 
standard-list:  simple list with title and metadata (  example) 
  thumbnail-list:  list with image preview for facts of the services "image" and "slideshow" (  example) 
 
If you want to allow users to choose between standard and thumbnail list, you need to enable this option. By doing so, users are provided with a drop-down menu as soon as they create a folder. 
  
  In order to enable the thumbnail list option, proceed as follows: 
  |1| Choose "Interface from the main menu. 
  |2| Click on the "modify"-button in the row "Define list columns".    |3| Click on the "list"-button in the row "Structure". 
  |4| Click in the checkbox in the row "Thumbnail list". 
  
  
  
  
  
|5| Finally, click on "Save changes". 
   
 
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