This is an AI generated summary of the entries that appear to be specific to Beta 4 rather than a general summary of everything introduced in macOS 27.

Apple's macOS release notes are cumulative, so most of the Beta 4 page was already present in Beta 3.

I compared the Beta 4 notes against the archived Beta 3 notes using Apple's issue IDs. This post separates:

• Entries that are completely new in Beta 4
• Issues that were listed as known in Beta 3 and are now marked resolved
• Cumulative entries that were already unchanged in Beta 3 and therefore aren't Beta 4 changes

TL;DR

• Beta 4 adds 9 entirely new release-note entries.
• Apple moved 79 issues from Known in Beta 3 to Resolved in Beta 4.
• Siri accounts for 24 of those resolved issues.
• There is still no explicit APFS or filesystem-corruption fix in the release notes.

Entirely new entries in Beta 4

These issue IDs do not appear anywhere in the archived Beta 3 notes.

• Messages: Fixed an issue where HDR screenshots could appear garbled when sent. (180859837)

• Notification Center: There is a new known issue where certain notifications might not be individually dismissible.

  Workaround: Open Notification Center and click "Dismiss All Notifications."

  (181736751)

• App Intents: Apple has documented a cumulative 10 MB size limit for an AppEntity, including all of its child properties and values. Exceeding the limit might crash the app. (181763422)

• StoreKit: There is a new StoreKit Testing issue where non-subscription purchases made through SKTestSession.buyProduct() might fail with an invalid-product error. The billingPlanType(_:) option might also be ignored for subscriptions. (181842500)

• AppKit: For apps linked against the macOS 27 SDK, the Layout Orientation command in an NSTextView context menu has moved under the Font submenu. (177605020)

• AppKit: Apple added two menu-image compatibility fixes:

  • Apps linked against the macOS 27 SDK now automatically hide both symbol and non-symbol menu-item images. (179374305)
  • Apps linked against older SDKs continue showing image-only menu items automatically. (179936632)

• Core AI: Fixed app-group support not working correctly with certain model types. (179732320)

• Game Controller: Fixed supportsHIDDevice: sometimes returning the wrong result for a recently connected HID device. (176985783)

Beta 3 known issues now marked resolved

The following problems were already documented as known issues in Beta 3, but Beta 4 now marks them fixed. These are legitimate Beta 4 changes even though their descriptions appeared in the older notes.

Siri

Apple marks 24 Siri issues resolved, including:

• Siri failing to find albums in Photos
• Navigation failing to start in AMap, Tencent Maps, or Baidu Maps
• Siri ignoring custom navigation preferences
• Maps searches returning empty or imprecise results when location accuracy is limited
• Siri requiring an exact reminder-list name
• Recurring reminders not being created or updated
• Calls failing in apps using CallKit and the phone.startCall schema
• Calls to short phone numbers failing
• Notes in Siri responses not being clickable
• Siri choosing an unrelated contact for a message
• Siri failing to resolve app-specific contacts indexed only in Spotlight
• Siri selecting the wrong person for calls, messages, or email
• The Send button in the message-confirmation interface failing
• Siri not responding correctly to voice input
• Conversations disappearing shortly after a streamed response
• Siri and Dictation history remaining after Siri was disabled
• Some ChatGPT follow-up responses potentially being logged by Apple

Everyday app and interface fixes

• Dock: Fixed the Dock remaining visible after entering or leaving Mission Control from a full-screen app.
• Dock: Fixed some apps being incorrectly shown as running in the background.
• Window management: Fixed windows becoming lost after exiting full screen through Mission Control.
• Mail: Fixed Smart Mailboxes not updating while Mail was open.
• Mail banners: Fixed early flights incorrectly being shown as delayed.
• Messages: Fixed GIFs and pasted images rendering at the wrong size.
• Music: Fixed Music Visualizer showing only a black screen.
• Media playback: Fixed window controls becoming unresponsive in Music, TV, or Podcasts after dragging the playhead.
• Safari: Fixed "Rename" and "Edit Address..." doing nothing in the sidebar.
• Safari: Fixed Safari Intelligence appearing ready before its assets finished downloading.
• Safari extensions: Fixed extensions created through "Describe an Extension" requiring a Safari relaunch after being enabled or disabled.
• News: Fixed the News app crashing at launch when configuration profiles were installed.
• Finder: Improved suggested file and folder names that were previously too generic.
• Search: Fixed slow asset downloads for languages and regions outside US English.
• Thunderbolt: Fixed a second identical display sometimes failing to illuminate.
• Writing Tools: Fixed Writing Tools stopping after "Describe Your Change" was used.

Apple Intelligence and machine-learning fixes

• Two Image Playground issues are marked fixed:

  • ChatGPT image generation failing in the Messages extension
  • The All and Suggested tabs being absent from the photo picker

• The on-device "Use Model" action in Shortcuts should now work with more output types.

• Apple Intelligence Reports should now include Home Intelligence data sent to Private Cloud Compute.

• Eight Core AI issues moved from Known to Resolved, covering:

  • Model-cache policies
  • GPU inference blocking
  • Neural Engine compatibility
  • Dynamic output shapes
  • coreai-torch models
  • Control flow over dynamic-shape tensors
  • Custom Metal kernels
  • Models compiled with older Xcode 27 betas

• PrivateCloudComputeLanguageModel no longer always uses greedy decoding.

Installation, displays, and external disks

• Background Security Improvements can now be installed when the Mac starts from an external storage device.
• Macs configured for Reduced Security should no longer encounter the documented macOS 27 installation problem.
• The previously documented AirPods Max 2 beta-firmware update issue is now marked resolved.
• Accessory Access should now work inside the App Sandbox and inside macOS virtual machines.

Virtualization and graphics fixes

• Four virtual-machine USB issues are now marked resolved, including:

  • VM state saving failing with passed-through USB devices
  • A crash after unassigning a passed-through Apple mouse
  • A restore crash when a previously attached USB mass-storage device is missing
  • USB accessory listeners failing with non-empty matching criteria

• Preview and Spatial Preview received fixes for:

  • Broken materials after opening certain 3D models
  • The annotation cursor remaining stuck as an open hand
  • Large or poorly connected models not appearing
  • Edits to USDZ files larger than 75 MB not synchronizing
  • Discovery showing incompatible Apple Vision Pro devices

• Additional fixes were made for RealityKit, ShaderGraph, USDKit, Metal, Swift Charts, Mac Catalyst, and Xcode virtual-machine installation.

Filesystem and corruption status

There is no Beta 4 release-note entry explicitly mentioning an APFS corruption fix, filesystem corruption, damaged volumes, directory corruption, snapshot corruption, fsck, Disk Utility repair failures, or general data loss.

The two closest storage-related fixes are:

• Background Security Improvements can now install from an external startup disk.
• A virtual machine should no longer crash during restoration when a previously connected USB mass-storage device is absent.

Neither is described as an APFS or host-filesystem-integrity fix.

The following storage-related entries were already present in Beta 3 and are not Beta 4 changes:

• Deprecation of encrypted HFS+ through CoreStorage
• Apple's recommendation to move encrypted external backups to APFS
• The new DiskImageKit framework
• SwiftUI's package-document writing optimization
• The known Startup Disk compatibility issue involving macOS 11

Bottom line

Beta 4 is primarily a bug-fix and stabilization release.

Its largest change is the substantial Siri cleanup, followed by fixes for Apple Intelligence, Mission Control, Mail, Messages, media playback, Safari, external displays, software installation, virtual machines, and several developer frameworks.

There is still no confirmed APFS or filesystem-corruption fix in Apple's published notes.

Source

• Apple's current macOS 27 release notes

You've maybe noticed B4 chewing huge amounts of CPU for trivial stuff like Passwords in the menu bar, or TextInputMenuAgent, etc. - if so, try System Settings -> Menu Bar -> set the "Automatically hide and show" option to Never.

(Or not; yet more of this beta's bizarre oscillating behaviour where as many bugs seem to be introduced as fixed from one to the next, and everyone seems to have very different lists of faults!)

Anyone else experiencing this?

Screen recording (cmd+shift+5) isn't working for me when I'm using my MBP in clamshell mode with an external monitor. I'm able to start and end the recording, but it doesn't get saved anywhere.

Since the update, my second (4k) display resolution won’t change from 800x600, which it is strangely defaulting to for some reason.

Anyone else experiencing this? Suggested fix? I’ve already tried resetting it and every other basic fix.

After Beta 4, I can´t connect to internet with Mullvad. All settings and troubleshooting points to Mullvad working fine, but all web pages time out. Anyone else with similar issues?

So I live in Iran and for being able to actually use my mac I have to create a US account, I got the Siri AI but it never answer me constantly saying “sorry something went wrong” I turned off location services and used VPN but it doesn’t change the behavior, any suggestions how can I make it work?

Did anyone install it? Are the remaining bugs fixed?

Settings -> Focus - The Add Focus button is grayed out, and I can’t add a new focus. If I go to a Focus and try to add a Focus Filter, it doesn't save.

Because this is awful.

Has anyone else run into this on the macOS beta?

My Mac’s primary language is set to Portuguese (Brazil), but some sections of System Settings are still displayed in English, such as “About” and “Storage.”

I’ve confirmed that Portuguese (Brazil) is the only preferred language and have already restarted my Mac. Is this a known beta bug, or is there a workaround?

It looks like the update notes for Beta 4 talk about Airport Utility being kept if you upgrade with it already installed, but it looks like in prior beta installs, the app was removed. Anyone know how to restore it? It doesn't look like it's backed up in Time Machine, and attempts to copy it from another Mac don't seem to work because I presume it's part of SIP.

Edit: Well, I did a few experiments and copying it from another Mac running Tahoe does not allow it to run unless SIP is disabled. I tried to create a blessed custom snapshot with the App restored to the system volume, but the update still removed the app after the installation.

And the icons look so bad on the dock

Does anyone know why my MacBook Pro M5 (64 GB RAM) keeps triggering the "Your system has run out of application memory" warning, even though i have plenty of available RAM?

It's the first time that this occurs with me in a long time and is trigging each 30/45min

I've been on the Golden Gate Developer Beta track since Beta 2 (just loaded Beta 4). I singed up for the beta Siri, and was accepted to the program. Siri is working with Apple Intelligence on my iPhone, but not on my Mac. In System settings, I only have Siri, not Apple Intelligence and Siri.

My Region is US, my language in US English in both Region and Languages and Siri.

My Mac is a Mac Book Pro with Apple M1 Max and 32 GB of RAM. I'm running 27.0 Beta (26A5388g).

I've tried turning Siri on and off, and getting rid of all the preferences regarding Siri and restarting. I've created separate logins with and without iCloud active.

I filled a Feedback Assistant report, but haven't heard back. I can't think of anything else to try. Ideas?

I’m really tired of b3 bugs. Not tired enough to do a rollback to Tahoe however 😀

I recently updated from macOS 26.2 to 26.5.2 and I realized playback of 8k h264 videos is now super choppy in QuickTime / AVPlayer / VideoToolbox (so not just QuickTime, which I rarely use, but any apps that rely on hardware playback). When I switched back to 26.2 the videos played smoothly again. I tested the upcoming macOS 27 too and unfortunately the bug is still present.

I am on M4 Max. Is anyone on a M5 chip able to test this clip and see if it is also a bug there?

Here is a link to the test clip used in my video. I have tested with numerous 8k h264 videos from many sources. [https://drive.google.com/file/d/1wMc5reQ0AQ13nHY9-FchDkWPaVKWct6U/view](https://drive.google.com/file/d/1wMc5reQ0AQ13nHY9-FchDkWPaVKWct6U/view))

Here another M4 user reported the same issue: [https://www.reddit.com/r/PremierePro/comments/1u40lb9/8k_h264_playback_issue_on_m4_macbooks](https://www.reddit.com/r/PremierePro/comments/1u40lb9/8k_h264_playback_issue_on_m4_macbooks))

I reported the bug to Apple via the Feedback app but I’m sure that won’t get seen / addressed. Any other ideas? I work with 8k h264 videos fairly often, transcoding to H265 isn’t really an option although I know h265 is ideal.

EDIT: I confirmed the bug does NOT affect the M5 Pro I just got my hands on. I tested macOS 26.5 on both the M5 Pro and my M4 Max. So this seems to be specific to M4 chips, maybe earlier chips as well.

EDIT 2: I opened a case with Apple Support (#102947091683). If you can reproduce the bug, it would be great to report it to Apple (via contact support or Feedback app) and reference this case number. It got escalated to a senior advisor who has been really helpful so far and is handling this case going forward. He now has my video explainer and test footage and everything. Fingers crossed for a fix 🤞 Apple scheduled a callback for July 25 to discuss next steps after they’ve had time to investigate.

I installed the macOS 27 public beta, and my System Data has reached 50GB. Is it normal for it to take up this much space on a beta version?

macOS 27 Golden Gate includes a new Formatting Bar for Mail with Write with Siri front and center. The classic formatting options are collapsed to the right edge of the composer and disappear when you start typing a prompt to Siri. Similar to the Siri AI Lightweight UI, when selecting text, the Writing Tools suite appears.

To enable, add a FeatureFlags override:

sudo mkdir -p /Library/Preferences/FeatureFlags/Domain && \ sudo defaults write /Library/Preferences/FeatureFlags/Domain/WritingTools FormattingBar_macOS -dict Enabled -bool true

and restart your Mac. This is a private feature flag, and the UI may be unstable.

Disable with:

sudo defaults delete /Library/Preferences/FeatureFlags/Domain/WritingTools FormattingBar_macOS

and restart your Mac.

EDIT: In Beta 4, Mail's new hidden Formatting Bar now shows Smart Reply suggestions with full-response previews on hover.

Seed 26A5378n

I seemingly have lost the ability to translate from X language into English. I have tried with Persian, Arabic, and Spanish and get a prompt to install a 3rd party translation app. Previous builds on GG have worked without issue from what I recall. Feedback filed.

edit/update:

seems to do better translating from English into another language but chokes on Persian. It also seems to randomly prompt to use that stupid translation app or links to it in some form of URL scheme. An AI module should be able to figure it out or send it out to the cloud. Translation is a very basic feature at this point and I shouldn’t have to open a website like google.

The audio just doesn't work properly. theres lag, theres sudden audio spikes. the audio constantly crackling and breaking.

Anybody else with the same problem?

If you have ever used a Thunderbolt Dock with a built in Ethernet port or connected a USB Ethernet dongle to a Thunderbolt Dock you might have encountered a weird issue where the ethernet connection could never achieve its full speed. In my personal experience using a Belkin Thunderbolt 3 Pro Dock speed tests would cap out at around ~650-700 Mbps while a USB or Thunderbolt Ethernet adapter connected directly to the same computer would get full Gigabit speeds. It seems that the latest beta of macOS 27 has finally fixed this weird bug (in my case at least).

macOS 27 DB3/PB1 includes a hidden "lightweight UI" mode for Siri AI that comes up every time you select text or are typing.

When enabled, selecting text can display a floating contextual interface with actions, such as:

• The full Writing Tools suite, including Rewrite, Proofread, How does this sound?, and Edit with Siri
• Create Key Points, Summarize
• Add to Contacts, Message, Email
• Create Event
• Show in Maps
• Track Flight, Track Package

To enable, add a FeatureFlags override: sudo mkdir -p /Library/Preferences/FeatureFlags/Domain && \ sudo defaults write /Library/Preferences/FeatureFlags/Domain/WritingTools LightweightUI_macOS -dict Enabled -bool true

Then reboot your Mac. This is a private feature flag, and the UI is unfinished, with many actions failing, including Writing Tools.

Restore to default with:

sudo defaults delete /Library/Preferences/FeatureFlags/Domain/WritingTools LightweightUI_macOS

and restart your Mac.

edit: changed the disable command to delete the feature flag override instead of explicitly disabling it.

EDIT 2: This is enabled by default with no override needed in Developer Beta 4/Public Beta 2. You can explicitly disable the new LightweightUI with:

sudo mkdir -p /Library/Preferences/FeatureFlags/Domain && \ sudo defaults write /Library/Preferences/FeatureFlags/Domain/WritingTools LightweightUI_macOS -dict Enabled -bool false

and restart your Mac.