I just installed this 0.8 rc version, and it's a great work.
I found two minor bugs. I'm not a ease with the tracking system, so I don't know if they are already submitted somewhere, or already fixed in the repo.
1- Encoding error in from field, in the read mode, and compose mode. (ok for the mailbox view).
Sender name : " Világ Ãœgyfélszolgálat " instead of " Világ Ügyfélszolgálat " for example (it's hungarian). I don't know if utf-8 or other encoding.
2- [for this one, maybe I don't know how to use it] At the end of installation, the SMTP validator didn't worked. Error message like "Not OK: Incorrect sender or recipient". If I set some random string or nothing, it is the same. But I can perfectly send mails after, in roundcube.
I must admin I don't know what is a recipient exactly in this context, and how it should like. Maybe it should be more explicit.
I tried to help, I hope it will.