may be used to change the current selection. <HOME> and <END> are used to go to
the first/last sibling of the current item. '+', '-' and '*' expand, collapse
and toggle the current branch. Note, however, that <DEL> and <INS> keys do
-nothing by default, but it is usual to associate them with deleting item from
+nothing by default, but it is common to associate them with deleting an item from
a tree and inserting a new one into it.