Raise a LoginError if expected cookie not set from SE OpenID login.
Raise a LoginError if expected cookie not set from SE OpenID login.

Raise an error if an HTTP error is returned in _post_with_fkey().

Charcoal-SE/ChatExchange,hichris1234/ChatExchange,ByteCommander/ChatExchange6,hichris1234/ChatExchange,Charcoal-SE/ChatExchange,ByteCommander/ChatExchange6