This makes adding black borders to the photo invisible.  What's the plan for this?  It seems to me that if we do this, we should remove those two border options and allow only white borders.   If you land it like this, you should at least file a followup bug to remove the black border options.

You may need to ask Patryk what the right thing to do here is.  I think a recent patch has also changed the background color of the main display window, so black borders will never show anyway.