Navigation mesh example - box becomes trapped inside obstacle

In the tutorial example below I do the following:

  1. open the door;
  2. move the box to the space where the door previously existed;
  3. toggle the door closed and open again.

The box then appears to be trapped. What is the cause of this?

I asked exactly the same question before. See Cedric’s reply: Navmesh - Agent stuck with dynamic obstacle - #4 by Cedric


Thank you Slin.