As I don't know the real cause I'll explain my problem. With epiphany or Mozilla I can read a gz compressed text document directly within the browser, but with epiphnay-webkit I can't. it downloads the document. For example I access http://launchpadlibrarian.net/27500212/gnome-bluetooth_2.27.5-1ubuntu1.diff.gz
I don't think the libsoup backend currently supports "Content-Encoding: gzip". That server appears to be unconditionally sending content with that content-encoding, even when the client does not include "gzip" in the "Accept-Encoding" header. I think that's technically a violation of the RFC. Boo.
Right, since the Content-Type here is 'text/plain' I think this is just the server ignoring us when we say we don't support 'gzip' encoding, and that this would just work if the server wasn't buggy or if we supported that. Let's mark this as a dupe of 25855. *** This bug has been marked as a duplicate of 25855 ***