macOS Tahoe 26.6 Release Notes
Update your apps to use new features, and test your apps against API changes.
Overview
The macOS 26.6 SDK provides support to develop apps for Mac computers running macOS Tahoe 26.6. The SDK comes bundled with Xcode 26.6, available from the Mac App Store. For information on the compatibility requirements for Xcode 26.6, see Xcode 26.6 Release Notes.
CoreStorage
Deprecations
Encrypted HFS+ (CoreStorage) is deprecated and will not be supported in macOS 28. If you use Encrypted HFS+ backups on external drives, begin backing up to encrypted APFS-formatted external drives instead. (175892336)
Ecosystem
Resolved Issues
Fixed: macOS deprecation notifications incorrectly identify a host app as Intel-only when a system plugin loader, such as a Color Picker or Print Dialog Extension, loads x86 code into the host process. (174841181) (FB22512943)
HealthKit
Resolved Issues
Fixed: Temporally-weighted average statistics queries for discrete quantity types such as Resting Heart Rate may return erroneously high values when samples overlap in time. (178157672)
Messages
Resolved Issues
Fixed: HDR screenshots might appear garbled when sent in Messages. (180859837)