Highlight ID Occurrences in Text Mode
To see the occurrences of an ID in an XML document in the Text mode,
      place the cursor inside the ID declaration or reference. The occurrences are marked in the
      vertical side bar at the right of the editor. Click a marker on the side bar to jump to the
      occurrence that it corresponds to. The occurrences are also highlighted in the editing
        area.
  Note: 
Highlighted ID declarations are rendered with a different color than highlighted
        ID references. To customize
          these colors or disable this feature, open the
            Preferences dialog box  and go to .
