Comment 3 for bug 1796596

The current situation is not a good solution. I don't think it's a good idea pop up a warning that there are objects on a layer that is no longer defined and then not opening the board. I see one of two possibilities: open the board and warn the user that there are objects on undefined layers or silently remove the objects from undefined layers and load the remainder of the board as is. We need to choose a solution and implement it. My preference would be to warn the user with an option to remove the orphaned objects on save.