Add cookie to websocket requests
According to @Nazar65's research, Slack now requires cookies to be added to websocket requests. Unlike the quickfix from #584, this MR sets the `Cookie' header directly to work correctly with multiple accounts. Should fix issues #584, #585
Tested and so far it seems to work fine. Thank you :-)
Actually, it looks like it make the problem appear less often. After ~8 hours of connection, I get the 429 errors again... Don't you @jumper047 ?
Actually, quitting emacs and going back seems to make the 429 error go away for a few hours again.
@Konubinix yep, same for me. No matter what approach I used - this PR, or url-cookie-store from issue, result is the same: it works some time, then it stops working(429 errors or recurring reconnects), and works again after emacs restart.
thanks @jumper047 for your contribution, it got in master via isamert repo. Also the lc cookie is necessary now!