I'm trying to look at the discussions that were moved to chat but it gives me a "Page Not Found" error. Is it because it was too old?
Chatrooms for comments get auto-deleted after a week of inactivity. This fits with the ephemeral nature of comments on the whole.
I can still see the chat (this may possibly be a function of reputation). Anyway, here it is. Click to embiggen.
The only thing missing off the bottom of the screen is the "This chat room has been deleted for inactivity" message.