Works fine for me on that version, though in my case I'm using SSO. Does your reverse proxy reply with proper Content-Type header? It seems like it doesn't considering you get a HTML back for a (potential) JSON request, at least that's what I would assume. Error seems to hint as much.
cannot use 'in' operator to search for "ban_view_token" in <!doctype html><...
Thread
Comment by @MrRubberDucky
Content-Typeheader? It seems like it doesn't considering you get a HTML back for a (potential) JSON request, at least that's what I would assume. Error seems to hint as much.