I'd really like to get to the bottom of this. On a clean-history browser, I still don't get any errors without this patch. In fact, django-debug-toolbar shows the csrftoken cookie variable in the Request Vars section, and the dev server keeps saying:
... "POST /pagedown/preview/ HTTP/1.1" 200 ...
Can you publish a small test repository (perhaps a mezzanine demo site) in which this patch is required?
Sure, I've PM'ed you the URL. But actually the pagedown code never gets that far because of #11 so now you get a chance to meet that one in person as well. Unless your browser is radically different than mine ;) .
So check that one out if you don't mind, and I will work around it afterwards so we can proceed with this one.
Tuk, to clean up the pull request, you can graft the non-merge commits in this pull request onto the tip of my repo, then fold/squash them into one commit using the histedit extension. I'd do it myself, but then the resulting commit would be authored by me.