Apple released the 5th developer preview of macOS Sierra 10.12.5 on Monday. The patch notes say nothing besides the boilerplate note that the release. “improves the stability, compatibility, and security of your Mac.”
The company has been on an aggressive release schedule for developer previews of macOS 10.12.5, with the 4th release coming just last week.
Developer Preview of macOS Sierra
Developers can download the update through the Apple Developer Connection. Macs that have already been included in the beta program can also download the update through the Mac App Store.