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Click on the +/- icon to show and hide.
Use the TAB key to move the focus from one list to the next where FF&E's/occurences are found.
Using the arrow keys. Using the following keyboard shortcuts:
Shortcut | Function |
  | Focus on the tree on the right-hand side |
  | Focus on the active tab on the left-hand side |
  | Select next tab |
  | Select previous tab |
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