No good way, no. What you can do is look at the Server: header that the web server sends you, and guess the newline convention from that. However, test if the server auto-converts the newlie convention when you fix your content-type.

IMHO the best way to fix this is on the server side.

Also, note the update in the grandparent node to this -- I had a \cM where I wanted a \cJ.