Apple Seeds Second macOS Monterey 12.3 Beta to Developers - MacRumors
Skip to Content

Apple Seeds Second macOS Monterey 12.3 Beta to Developers

Apple today seeded the second beta of an upcoming macOS macOS Monterey 12.3 update to developers for testing purposes, with the new software coming two weeks after the release of the first macOS Monterey 12.3 beta.

macOS Monterey on MBP Feature
Registered developers can download the beta through the Apple Developer Center and after the appropriate profile is installed, betas will be available through the Software Update mechanism in System Preferences.

macOS Monterey 12.3 is a major update that introduces Universal Control, a feature that Apple first teased at WWDC and then delayed for several months. ‌Universal Control‌ is designed to allow you to use a single mouse/trackpad and keyboard across multiple Macs and iPads (with iPads running iPadOS 15.4).

After updating your devices to macOS 12.3 and iPadOS 15.4, ‌Universal Control‌ works automatically, allowing your Mac's cursor and keyboard to work on the iPad and vice versa. It's simple and intuitive to use, and the second macOS 12.3 update adds an icon that you'll see in the menu bar to denote that it's activated.

maOS Monterey 12.3 adds support for updating the AirPods firmware when the earbuds are connected to a Mac, plus it deprecates kernel extensions used by Dropbox and Microsoft OneDrive, and it eliminates Python 2, with Apple instructing developers to use an alternative scripting language like Python 3 going forward.

Related Forum: macOS Monterey

Popular Stories

iOS 27 Next to iPhone

Here's When iOS 27 Rolls Out Today in Every Time Zone [Update: It's Out]

Sunday September 13, 2026 3:00 am PDT by
Update 10:04 a.m.: iOS 27 is rolling out now, though it may take a bit for all users to see it, so keep checking! Apple is about to release iOS 27, which will finally deliver more advanced Siri AI capabilities as well as a variety of other refinements, improvements, and new features to iPhones. It's Apple's biggest software update of the year, and Apple announced at Wednesday's iPhone event...
iOS 27 Icon iPhone

iOS 27 Available Now With These 8 New Features

Monday September 14, 2026 9:00 am PDT by
Update — 10 a.m. Pacific Time: Apple has released iOS 27. During its iPhone 18 Pro and iPhone Duo event last week, Apple announced that iOS 27 will be released widely on Monday, September 14. iOS 27 should be available around 10 a.m. Pacific Time / 1 p.m. Eastern Time today via the Settings app, under General → Software Update. Below, we have highlighted eight new features and...
Apple iCloud Plus expansion hero

iCloud+ Now Includes Apple TV, Apple Arcade, and Curated Apple Music Stations in Over 100 Countries

Tuesday September 15, 2026 1:43 am PDT by
Apple today announced a new subscription initiative that turns paid iCloud+ subscriptions into a broader services bundle in more than 100 countries. In select countries, Apple says every paid iCloud+ plan, including the cheapest 50GB tier, now includes Apple TV and Apple Arcade "at no additional cost," while family sharing extends the storage, TV and Arcade access to up to five people....

Top Rated Comments

Realityck Avatar
60 months ago
Good, now can test out several issues that the first beta had.

macOS 12.3 beta 2 (21E5206e)
Score: 5 Votes (Like | Disagree)
Realityck Avatar
60 months ago
Beta 2
Safari is Version 15.4 (17613.1.16.1.3)

System Firmware Version: 7459.100.494.121.1 (M1 based Macs)

Darwin Kernel Version 21.4.0: Sat Jan 29 03:25:23 PST 2022
; root:xnu-8020.100.417.0.4~31/RELEASE_ARM64_T8101

Beta 1
Safari Version 15.4 (17613.1.14.1.7)

System Firmware Version: 7459.100.487.115.1 (M1 based Macs)

Darwin Kernel Version 21.4.0: Tue Jan 18 13:02:08 PST 2022
; root:xnu 8020.100.406.0.1~18/RELEASE_ARM64_T8101
Score: 4 Votes (Like | Disagree)
60 months ago
The icon for Displays has changed.....




Attachment Image
Score: 3 Votes (Like | Disagree)
60 months ago
Score: 3 Votes (Like | Disagree)
Realityck Avatar
60 months ago
[SPOILER="macOS Monterey 12.3 Beta 2 Release Notes"]
General
Resolved in macOS Monterey 12.3 Beta 2

* Fixed: If your Mac currently has macOS Catalina installed, installing macOS Monterey 12.3 beta or macOS Big Sur 11.6.4 beta on a volume with FileVault enabled might cause a boot loop when attempting to log back into the previous volume. (88163545)

iCloud
Resolved in macOS Monterey 12.3 Beta 2

* Fixed: iCloud+ Custom Email Domain set up flow can’t be initiated from the iCloud settings in System Preferences. (85212987, 88045659)

Kernel
Deprecations

* The kernel extensions used by Dropbox Desktop Application and Microsoft OneDrive are no longer available. Both service providers have replacements for this functionality; Dropbox is currently in beta. (85890896)

LibreSSL
Known Issues

* LibreSSL 3.3 has changed the default digest type of openssl enc Terminal command to SHA256. Files previously encrypted with an older version of OpenSSL might fail to decrypt. (87763613)
Workaround: The openssl enc command should be run by adding the -md md5argument.

Mobile Software Update
Resolved in macOS Monterey 12.3 Beta 2

* Fixed: Virtual machines running on Apple silicon are unable to install macOS 12.3 beta. (88106053)

Known Issues

* Installing to an empty volume from macOS Recovery might fail. (87730473)
Workaround: Use a different version of macOS Recovery. For Intel-based Macs, boot using Option-Command-R; for Macs with Apple silicon, double-press and hold the power button.

Python
Deprecations

* Python 2.7 was removed from macOS in this update. Developers should use Python 3 or an alternative language instead. (39795874)

ScreenCaptureKit
Known Issues

* In ScreenCaptureKit ('https://developer.apple.com/documentation/screencapturekit'), if an origin other than (0,0) is specified in the destinationRect ('https://developer.apple.com/documentation/screencapturekit/scstreamconfiguration/3919822-destinationrect')or sourceRect ('https://developer.apple.com/documentation/screencapturekit/scstreamconfiguration/3919829-sourcerect'), the contentRect is incorrect. (87363220)

Universal Control
Known Issues

* Unexpected disconnections might occur on initial connection. (88106231)
Workaround: Sleep, then wake the device, and try again.
* Drag-and-drop scenarios might not work for some file types and apps. (88106322)
* Some third-party keyboards and mice might encounter issues when using additional functionality, like scroll wheels. (88106362)

WebKit
Known Issues

* Using the App Store might lead to an auththentication loop in which the HTML sheet has no content. (87850345)
Workaround: Install WebKitRoot.tar.

Deprecations

* Support for inline viewing of PostScript files was removed. (88172449)

[/SPOILER]
Score: 3 Votes (Like | Disagree)
alanvitek Avatar
60 months ago

@alanvitek It's likely they will never fix it because my feedback has been updated with this months ago:
"Investigation finished. Functionality given according to current design."
That’s ridiculous. Current design meaning overlapping buttons? Yea I’m sure that design pattern is in Apples HIG smh
Score: 2 Votes (Like | Disagree)