When recovering the session, error with invalid fiducials

[sotodela]

When recovering the session an error : "Invalid fiducials" when trying to start neuronavigation
After loading markers files again the navigation works, however if there is not saved markers, the image fiducials need to be selected again.

[vhosouza]

@Rakhesis suggested to try this and see if the error appears:

1. Start session
2. Load image
3. Create fiducials
4. Save new project (or save over existing project)
5. Restore the session

This might be caused by the fiducials not being saved in the project.