If you choose an element that is relatively small at the edge of the screen, the tour step is repositioned to stay on the screen, but the arrow element pointing at the intended element does not quite get back to the center of that element.
Here is an example:
Here is a screenshot of the code:
Fix for issue #588
Position the arrow based on it’s previous positioning. Use the
difference it had from the halfway (50%) point and add that the the
previous calculation to properly determine it’s new position.