Bug fix; this was modifying origin header in place
Bug fix; this was modifying origin header in place

This was a reference to the same string, not a copy, so ended up modifying the origin header in place, causing the allow-origin header in the response to be wrong.  The POST was still going through but browser console showed an error.
nbgallery/nbgallery,nbgallery/nbgallery,nbgallery/nbgallery,nbgallery/nbgallery