The highlight displays in a bright color and may have a highlight icon in the upper left corner. Example:
If an icon is present, a note box is associated with the highlight. A note box allows you to view and/or add information to a highlight. To open the highlighted note box and view the default text, double-click on the highlight icon.
The highlight icon may cover text you wish to view. To move the highlight icon, right-click on it and select Unobstruct. The highlight icon is invisible until you move the mouse again.