In the Outline navigation panel, single-click highlights the item and double-click brings the cursor to the selected section or table. I see no reason for highlighting the item with the mouse (if the reason is to use the pop-up menu, right-click can be used), and this contradicts the expectations of the users that get used to web pages where navigation is done with single click. Instead, I suggest that single-click should bring the cursor to the section or table -- what now is done with double-click.
In addition, I see no reason to have items highlighted manually in this tree at all. I already filed a feature request suggesting that highlighting should be automatic depending on the cursor position in the Editor window.