so you were misled and confused by google into thinking you need a google account, if only for a while. they try hard to manipulate people. do you see the problem now? yes, you can fight the stream of lies and misdirections, or you can say "thanks, but no, thanks".
Assuming there are only 2 threads, Otherwise, that only shows the public threads.
UPDATE: wow, didn't know you can't even read messages without being google-user. Yeah, that's boorish a bit.
UPDATE2: turned out that's not true. You can read google group perfectly fine without signing in: https://groups.google.com/forum/#!forum/tmux-users