Comment 54 for bug 883459

I'm seeing this in 4.9.2 (Kubuntu 12.04 x86_64)
Several messages get duplicated when filtered, and very often the duplicate one has only the header, no body. When this error happens, only one duplicate is created for each message affected.
The duplicated message (the one without a body) is sometimes left in inbox and sometimes moved automatically to the filter destination folder along with the original message. Sometimes the duplicate stays in the inbox, but as soon as I click the inbox the message is moved automatically to the filter destination folder. Sometimes, it is moved only if I trigger the filters manually with CTRL+J.
Almost always I can delete both the original and the duplicate by pressing DEL. Sometimes, however, one of them can't be deleted. When I press DEL the selection goes to the next message, but the message I tried to delete remains where it was. I can then repeat this several times with that message and it will not go away. If I close KMail and reopen it, the problematic message is gone from the folder where it was.
I get my e-mails only from POP3 accounts (no IMAP) and they are locally stored in a maildir storage.