First macOS Tahoe 26.4 Beta Now Available for Developers

[MacRumors]

Apple today provided the first beta of an upcoming macOS Tahoe 26.4 update to developers for testing purposes, with the update coming just a few days after Apple launched macOS Tahoe 26.3.

Developers can download the macOS Tahoe 26.4 update by opening up the System Settings app, selecting the General category, and then choosing Software Update. Beta Updates will need to be enabled, and a free developer account is required.

macOS Tahoe 26.4 could introduce some new Siri features, though at least some of the capabilities that we were expecting have been delayed. The update is also expected to introduce new emoji characters.

The beta is available to developers right now, but a public beta is expected in the next week or two.

Article Link: First macOS Tahoe 26.4 Beta Now Available for Developers

 

[wellander1]

Any betas for 14 and 15?

 

[tywebb13]

build number is 25E5207k

others:

macOS 15.7.5 RC 1 (24G607)
macOS 14.8.5 RC 1 (23J407)
iOS 26.4 beta 1 (23E5207q)
iPadOS 26.4 beta 1 (23E5207q)
tvOS 26.4 beta 1 (23L5208m)
audioOS 26.4 beta 1 (23L5208m)
visionOS 26.4 beta 1 (23O5209m)
watchOS 26.4 beta 1 (23T5209m)

 

[ericfroemling]

Compact tabs is back 🙂

 

[Tnanman]

Compact tabs is back 🙂View attachment 2605555

FINALLY.

I'll slow down on my complaining about Tahoe now lol

 

[JosephAW]

Installed Tahoe 26.3.0 on my M2 max studio external drive just to try it out, the interface still look wonky with text overlapping.
Checked file vault settings, but they were turned off, I thought Tahoe by default enabled encryption of home folder? 🙄

 

[Larsen2k4]

FINALLY.

I'll slow down on my complaining about Tahoe now lol

HOORAY!

 

[RRUK01!]

FINALLY.

I'll slow down on my complaining about Tahoe now lol

Can't see how to enable the Compact Tab Bar in Safari on Mac

 

[RRUK01!]

Compact tabs is back 🙂View attachment 2605555

Is that on the iPad or Mac.. apparently its supposed to be available on Mac Safari as well but not seeing the option on the Mac

 

[Lounge vibes 05]

Is that on the iPad or Mac.. apparently its supposed to be available on Mac Safari as well but not seeing the option on the Mac

It’s on both.
Safari in menu bar>Settings>Tabs

 

[auslad88]

I updated, but instant issues with external drives. I have a few RAID volumes formatted as macOS Journaled - all of these are readable but not writable - prompts to run disk utility in recovery mode - did that and still no joy. Even a Samsung T7 that is formatted macOS Journaled has the same error. I formatted as APFS and it works fine, but formatting back to Journaled throws the same error. so for some reason my upgrade does not like Journaled anymore :/.. I had also updated another Mac to 26.4 and has the same issue 🙂

 

[johnsawyercjs]

Checked file vault settings, but they were turned off, I thought Tahoe by default enabled encryption of home folder? 🙄

I don't think Apple has ever enabled FileVault by default, since the user needs to know if their drive is encrypted, and select settings that work for them. A full setup requires the user to establish a "backup" unlock method in case you forget your macOS password. You can choose to use your Apple ID to reset your Mac's password to unlock your drive, or use a local recovery key (a long string of random letters and numbers).

Also, FileVault has encrypted the entire drive for years. You might be remembering "Legacy FileVault," which encrypted only the Home folder, but Apple moved away from that years ago (around Mac OS X Lion) since it was prone to errors and didn't protect system files or temporary data stored outside the Home folder. Modern FileVault uses XTS-AES-128 encryption with a 256-bit key to secure the entire volume.

 

[avtoportret]

I updated, but instant issues with external drives. I have a few RAID volumes formatted as macOS Journaled - all of these are readable but not writable - prompts to run disk utility in recovery mode - did that and still no joy. Even a Samsung T7 that is formatted macOS Journaled has the same error. I formatted as APFS and it works fine, but formatting back to Journaled throws the same error. so for some reason my upgrade does not like Journaled anymore :/.. I had also updated another Mac to 26.4 and has the same issue 🙂

Same here!

 

[jtfolden]

I updated, but instant issues with external drives. I have a few RAID volumes formatted as macOS Journaled - all of these are readable but not writable - prompts to run disk utility in recovery mode - did that and still no joy. Even a Samsung T7 that is formatted macOS Journaled has the same error. I formatted as APFS and it works fine, but formatting back to Journaled throws the same error. so for some reason my upgrade does not like Journaled anymore :/.. I had also updated another Mac to 26.4 and has the same issue 🙂

Same here! :-( My external drives work fine on another Mac not running this beta, of course.

 

[tywebb13]

Same here! :-( My external drives work fine on another Mac not running this beta, of course.

maybe disable fsck_hfs before attaching drives?

• Kill the Process (Temporary Solution): If fsck_hfs is blocking access to a drive, use Activity Monitor or the Terminal command sudo killall fsck_hfs.
• Disable SIP and Rename fsck_hfs (System-wide):
  1. Boot into Recovery Mode (Command+R) and run csrutil disable in Terminal to disable System Integrity Protection.
  2. Restart the system.
  3. Rename the utility: sudo mv /sbin/fsck_hfs /sbin/fsck_hfs.disabled.
• Use fsck_hfs -n (No Repair): Run fsck_hfs with the -n flag, which forces it to never attempt to repair any damage found

 

[XMI]

From the release notes:

External Media​

Known Issues​

• HFS external media might fail to mount automatically. (168672160)
  
  Workaround: For macOS only, use CLI tool diskutil mount to attach the relevant disk device.

Here are the full release notes:

Spoiler: Tahoe 26.4 Beta Release Notes

AppKit​

Resolved Issues​

• Fixed: Window resize pointer does not follow the window's corner shape. (149726089)

Background Assets​

New Features​

• You can now check the status of an asset pack while offline by calling local<wbr>Status(of<wbr>Asset<wbr>Pack<wbr>With<wbr>ID🙂 or asset<wbr>Pack<wbr>Is<wbr>Available<wbr>Locally(with<wbr>ID🙂 on the shared asset pack manager. The former method returns all available status information. The latter returns only a Boolean value but can be called synchronously. Not all status information is available offline. (164498466)
• You can make the latest version of an asset pack available locally by calling ensure<wbr>Local<wbr>Availability(of:<wbr>require<wbr>Latest<wbr>Version🙂 on the shared asset pack manager and passing true to the should<wbr>Update parameter. (166237389)

Known Issues​

• Setting a URL override could break apps from the App Store that use Apple-Hosted Background Assets. (169558509)
  
  Workaround: Remove any URL override that you previously set before installing or using an app from the App Store.
• Apps might crash when downloading asset packs. (169648111)
  
  Workaround: If an app crashes due to this issue, then relaunch it. The app should then have local access to the asset pack that it was downloading when it crashed.

CoreMIDI​

New Features​

• Audio MIDI Setup now supports Network MIDI 2.0 sessions in the redesigned MIDI Network Setup panel. You can create MIDI 2.0 connections over your local network using UDP transport for Universal MIDI Packets, enabling both Legacy MIDI and MIDI 2.0 protocol communication. Network MIDI 2.0 sessions appear alongside existing RTP MIDI sessions and support automatic device discovery through mDNS and data integrity features for reliable wireless performance. (118728162)

External Boot​

Known Issues​

• When installing an external disk, some configurations of M1 Apple Silicon Macs might panic at boot. (170263142)
  
  Workaround: Install to a secondary volume in APFS container instead of external disk to validate secondary boot sequences.

External Media​

Known Issues​

• HFS external media might fail to mount automatically. (168672160)
  
  Workaround: For macOS only, use CLI tool diskutil mount to attach the relevant disk device.

Internet Accounts​

Known Issues​

• Exchange syncing for Calendar, Reminders and Notes might fail. (168082477)
  
  Workaround: To continue syncing Calendar and Reminders, disable Notes syncing in Internet Accounts.

Login​

Known Issues​

• Touch ID might not be available to unlock the screen of a standard user account after updating to this release. This occurs when FileVault is enabled and a standard user account is logged in prior to any administrator logging in following the update. (169743642)
  
  Workaround: An administrator user should sign in to the Mac before any standard users.

macOS Recovery​

Known Issues​

• When deleting a boot volume from the Activation Lock window in macOS Recovery, full erase functionality might not work. (170280070)
  
  Workaround: Use the "Erase All Content and Settings" functionality from the booted OS instead of triggering from recovery.

Networking​

Resolved Issues​

• Fixed: Multiple processes leak CFRun<wbr>Loop<wbr>Source objects when Automatic proxy configuration (PAC) or Auto proxy discovery are configured.
  
  For clients of the CFNetwork<wbr>Execute<wbr>Proxy<wbr>Auto<wbr>Configuration<wbr>URL and CFNetwork<wbr>Execute<wbr>Proxy<wbr>Auto<wbr>Configuration<wbr>Script API, please check to make sure your process is not working around the leak by overreleasing the CFRun<wbr>Loop<wbr>Source<wbr>Ref returned by those functions or the CFArray<wbr>Ref and CFError<wbr>Refpassed to the completion. (166839810) (FB21376045)

Resource fork​

Resolved Issues​

• On macOS 26.4 and later, file systems that do not natively support extended attributes restrict partial writes to the first 286 bytes of the resource fork extended attribute (com.apple.ResourceFork).
  
  To modify the resource fork, replace the entire 286-byte range, or write beyond the 286-byte offset. (156896699)

Rosetta​

Deprecations​

• As announced at WWDC in 2025, macOS Tahoe 26 is the last release to support Intel based Macs. Additionally, Rosetta support for apps will end after macOS 27. Starting in macOS Tahoe 26.4, users will be notified when they launch apps that use Rosetta of the upcoming incompatibility.
  
  During the beta period, the cadence of notifications will be accelerated, enabling Apple and developers to address any issues that might occur.
  
  There will continue to be support for older, unmaintained gaming titles leveraging Rosetta along with software running Intel binaries in Linux VMs.
  
  Organizations using a device management service can control the notification experience with the allow<wbr>Rosetta<wbr>Usage<wbr>Awareness key. (169228455)

StoreKit​

New Features​

• New fields revocation<wbr>Type and revocation<wbr>Percentage have been added to Transaction . (148858551)

SwiftUI​

Resolved Issues​

• Fixed: SwiftUI does not surface the latest .user<wbr>Activity as the current user activity. (163136831)
• Fixed: On macOS, a non-opaque window that hosts glass content will correctly update the backdrop content behind the glass even if the window is inactive. (166828089) (FB21375029)

Known Issues​

• Multiple implicit SwiftUI animations (triggered by Reality<wbr>View<wbr>Content<wbr>.animateor Entity<wbr>.animate) that modify a RealityKit component's properties, are combined only when the implicit animations target the same set of component properties.
  
  For example, if you initiate an implicit animation on Transform.scale and then initiate an implicit animation on Transform.scale and Transform.translation then the animations affecting the scale property will be independent of each other, and will not combine. In this case, the most recently initiated animation will overwrite the scale property. (169723142)
  
  Workaround: Ensure the same component properties are animated by subsequent implicit animations when possible.

Virtualization​

Resolved Issues​

• Fixed: On certain hardware configurations, new macOS Tahoe virtual machine installations may boot to a black screen. (169654019)

 

[XMI]

That HFS bug is pretty bad. I'm surprised they released this beta with such a serious bug.

For example, I just downloaded a DMG for some software to install, and got this:

 

[XMI]

A workaround for DMG files that won't mount:
hdiutil attach /Path/to/my.dmg
Replace /Path/to/my.dmg with the actual path to your DMG file.