The Compositor View Navigator shows a miniature version of Compositor View, with the nodes represented as solid white blocks and the visible portion outlined by a white rectangle.

Compositor View with Navigator in top-right corner
The Compositor View Navigator appears in the top-right corner of the interface. Use the Navigator to change the view efficiently. The following controls are available:
Options
Configuration. Click the Compositor View item on the left side of the State Sets Configuration dialog, then adjust the Radar settings. By default, the Navigator is initially minimized. To see it, drag its corner handle away from the edge of the Compositor View window.

Dragging the Navigator corner to open the Navigator