Sec-WebSocket-Extensions is a connection-level header.
Sec-WebSocket-Extensions is a connection-level header.

We don't support any extensions currently, but it's important that when acting as a proxy, we don't pass through this header, since it could result in the client and server negotiating extensions that the proxy doesn't understand and will botch.

mologie/capnproto,mologie/capnproto,mologie/capnproto