CiviMail: Bounce processing is broken with 5.67
Overview
CiviMail has implemented elaborated bounce processing features: When an email sent by CiviMail is not accepted by the recipient mail server, a bounce mail is sent to the bounce mail account configured in .../civicrm/admin/mailSettings&reset=1
The scheduled job fetch_bounces is parsing these bounce mails, using the verp address.
Normally, the bounce mail will be moved to a mail folder called /CiviMail/processed, if it can be traced to an email sent by CiviMail.
If however the bounce mail cannot be connected to a mail sent via CiviMail, the bounce mail is moved to /CiviMail/ignored
The connection is done via the verp address of the bounce mail, e.g.:
mail+b+<civicrm_mailing_job.id>+<civicrm_mailing_event_queue.id>+<hash>@<domain.org>
Since 5.67 it seems that this functionality is broken:
Any bounce mails are moved to the ignored folder. No bounce processing is performed anymore.
This issue might be a duplicate of #4775 (closed)
I have reproduced this on two different CiviCRM installs on WordPress.