I am aware that there has been a bug in earlier releases, causing
/var/lib/datasync/syncengine/attachments to grow infinitely. Build 343 is
supposed to fix that, but according to TID 7007456 only for new mails
("However, it will not clean up old orphaned attachments in
/var/lib/datasync/syncengine/attachments directory").

How can I clean up the directory one time, to get rid of all the old
attachments? As far as I have read here, just deleting the directory
seems not to be a good idea.

Thanks in advance,