The following was posted on the SpamSieve blog:

Version 2.9.26 of SpamSieve is now available. This is a free update that includes the following changes:

  • Works with Apple Mail under macOS 10.12.1. It’s easiest if you update to SpamSieve 2.9.26 before updating to 10.12.1. In any case, if you don’t see the SpamSieve commands in Apple Mail’s Message menu, be sure to choose Install Apple Mail Plug-In from the SpamSieve menu. Otherwise, with the SpamSieve plug-in not installed, Mail will move good messages to the spam mailbox without consulting SpamSieve.
  • Made various changes to improve SpamSieve’s filtering accuracy.
  • SpamSieve now tells Apple Mail’s junk filter when incoming messages are not junk (instead of only when they are junk). This should help prevent the confusing behavior of Mail displaying good messages in gold/brown text if its filter (or a server filter) disagreed with SpamSieve. Reminder: You can also have SpamSieve override the message text color by enabling AppleMailAllJunkMessagesUseBlackText in the esoteric preferences.
  • SpamSieve now uses the new os_log subsystem on macOS 10.12.
  • Adjusted the sizes of the Dock icon status indicators to work around a font change in macOS 10.12.
  • The version number of the Apple Mail plug-in is now synchronized with the version number of SpamSieve itself to reduce confusion for those using Mail Plugin Manager.
  • Added the Apple Mail - Mark Server Spam Messages as Read script.
  • Improved the following section of the manual:

  • Worked around a badly worded OS certificate error when checking for a software update.
  • Adjusted SpamSieve’s package resources to work around several code signing issues with macOS 10.12.
  • Fixed a bug where Apple Mail could repeatedly report the same error message.
  • Fixed a bug where the Portuguese localizer was not given credit in the About SpamSieve window.

SpamSieve 2.9.26 works with Mac OS X 10.6 through macOS 10.12 and requires an e-mail client. Older versions are available for older operating systems. For information about previous releases of SpamSieve, please see the version history.