Main Window - Tree | Expand Selected (keyboard only)                    Num +

 

 

This option expands the currently selected folder entry in the folder tree by showing any sub-folders. Double-clicking an expandable entry also performs this action.

 

If Indicate Expandable is checked, the folders which have sub-folders are marked with a '+'. If Indicate Thumbnails is checked, folders are color-coded to indicate the presence of thumbnails.