Apple has released macOS Tahoe 26.4 beta, a developer-focused update that delivers system fixes, new APIs, and clearer signals about the platform’s Intel-to-Apple-silicon transition. The release targets stability issues across networking, virtualization, SwiftUI, and AppKit, while also expanding tools for app developers building against Xcode 26.4.
The update ships with the macOS 26.4 SDK bundled in Xcode 26.4, enabling developers to test new features and prepare apps for future compatibility changes. Apple positions this beta as both a reliability update and a warning shot for teams still depending on Intel binaries and Rosetta.
AppKit, SwiftUI, and Virtualization Fixes Improve Stability
Apple addresses several long-standing UI and system issues in this beta. AppKit now correctly tracks window resize pointers to match window corner shapes, improving visual accuracy. SwiftUI fixes ensure the latest user activity surfaces correctly and glass-backed windows update content even when inactive.
Virtualization also sees a notable fix. Some macOS Tahoe virtual machines previously booted to a black screen on certain hardware. The 26.4 beta resolves that issue, making fresh VM installs more reliable for testing and CI workflows .
Background Assets Gain Offline Status Checks
The update expands Apple-Hosted Background Assets with new offline capabilities. Apps can now check whether an asset pack exists locally and request the latest version when connectivity returns. These changes help developers build more resilient offline-first experiences.
However, Apple flags a serious known issue: URL overrides can break App Store apps that rely on Apple-hosted background assets. Apple advises removing any overrides before installing or launching affected apps to avoid crashes or failed downloads .
Network MIDI 2.0 Arrives on macOS
Audio creators gain a major upgrade with Network MIDI 2.0 support. The redesigned MIDI Network Setup panel now allows MIDI 2.0 sessions over local networks using UDP transport. The system supports both legacy MIDI and MIDI 2.0 protocols, automatic device discovery via mDNS, and improved data integrity for wireless performance.
This update brings macOS closer to modern, low-latency audio workflows without third-party drivers or complex routing setups .
Rosetta Deprecation Warnings Become More Prominent
Apple continues its transition away from Intel. macOS Tahoe 26 remains the final release to support Intel Macs, and Rosetta support ends after macOS 27. Starting with macOS Tahoe 26.4, users now see warnings when launching apps that rely on Rosetta translation.
During the beta phase, Apple increases the frequency of these alerts to push developers toward native Apple-silicon builds. Enterprise teams can manage the notification experience using device-management keys, but the message is clear: Intel-only apps are on borrowed time .
macOS Tahoe 26.4 Beta Known Issues and Workarounds
Despite the fixes, Apple lists several important limitations in the beta:
- Exchange syncing may fail for Calendar, Reminders, and Notes
- Touch ID may not unlock standard user accounts on FileVault-enabled Macs until an admin signs in
- Some Apple-silicon Macs may panic when installing macOS on external disks
- HFS external drives may fail to auto-mount without manual diskutil commands
Apple provides workarounds for each issue and recommends testing carefully before wider deployment.
macOS Tahoe 26.4 beta is less about flashy features and more about direction. Apple tightens platform stability, expands developer control, and clearly signals the end of Intel compatibility. Developers who still rely on Rosetta or legacy APIs should treat this release as a final warning to modernize.
The public release timeline remains unannounced, but Apple expects developers to begin compatibility testing now using Xcode 26.4 and the macOS 26.4 SDK .
