I'm using roundcube version 1.2-rc and some e-mails are showing incorrectly, as shown here:
http://imgur.com/YaZFGU2

Steps:

1. Click Create e-mail

2. Add receipt

3. Add subject

4. Click Send

E-mail source-code: http://pastebin.com/TnN3UuGf

This seems not to happen if I change to Simple Text instead of HTML.

This seems not to happen if I write anything to the body of the e-mail.

This happens often with e-mails that has attachments, despite of body having a text.

On the e-mails list view, it always shows the message size as 1KB.