makinacorpus/django-leaflet — pull request #41 by manelclos (2013-11-07 13:54:15+00:00)
Title: Don't return null in onbeforeunload

Internet Explorer will always ask you if you want to leave the page if "null" is returned. See:

http://stackoverflow.com/questions/11793996/onbeforeunload-handler-says-null-in-ie