I received a private message.
In the notification email I read something like:
To reply to this message, visit: https://community.concretecms.com/account/messages/reply/inbox/<MESSAGE-ID>
That’s a 404.
It seems there isn’t a “reply” page anymore. If so, the best solution would be to do something like:
To view and reply to this message, visit: https://community.concretecms.com/account/messages/details/-1/<MESSAGE-ID>