This is mainly a maintenance release. Details are in the release notes.

The release is particularly interesting for users preferring the original IMAP approach to deleting emails, that is, marking emails as deleted and then expunging them (permanently) at a later time:

  • New: Hidden preference MmDeleteBehavior: moveToDeletedMessages, markAsDeleted, expunge, archive.
  • New: Hidden preference MmAutomaticExpungeBehavior: mailboxSwitch, never.
  • New: An Expunge toolbar button (which reuses the trash icon).
  • New: Accounts can be given their own deleteBehavior overriding the global default.