The position marker plugin queries the direction of "north" by computing latitude + 0.1 radians. This point can be off the screen, however, and the rendering function will early-out.

Skip the off-the-screen check for this northing point.

1. Resize the main Marble window to be no more than 768 pixels tall.
2. Switch to the Mercator view
3. Supply Marble with a valid position from any source
4. Zoom in to no more than five ticks from maximally-zoomed in
5. Ensure bug can be reproduced
6. Apply patch
7. Ensure position marker is visible under the above conditions