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macOS 27 Beta Hides Alternate Boot Volumes, Blocking Asahi Linux

Apple changed the recovery boot picker’s volume checks in the developer beta, preventing some Macs from seeing alternate operating systems.

Overview

  • Developers and users discovered in the macOS 27 Golden Gate developer beta that the recovery-mode boot picker and Startup Disk no longer detect some alternate partitions, and Asahi Linux reported the behavior as a bug and filed bug report FB22994760 with Apple.
  • Asahi says affected Linux partitions remain intact and that no user data has been lost, and it advises anyone who installed the beta to set a macOS 26 volume as the default Startup Disk to restore access to Asahi Linux.
  • Asahi has patched its installer so it will not run on macOS 27 until a workaround or an Apple fix is available, and the project says it will not support users who upgrade without a contingency plan.
  • Independent testing from coverage of the issue shows older macOS installations on separate partitions can also be made invisible, indicating a wider multi-OS impact beyond Asahi Linux.
  • The bug appears in an early developer beta so ordinary users should avoid installing it on daily-driver Macs and watch for fixes in upcoming macOS 27 betas that Apple can issue before the planned public release in the fall.