Apple Seeds Release Candidate Version macOS Monterey 12.3 Beta to Developers and Public Beta Testers - MacRumors
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Apple Seeds Release Candidate Version macOS Monterey 12.3 Beta to Developers and Public Beta Testers

Apple today seeded the release candidate version of an upcoming macOS Monterey 12.3 update to developers for testing purposes, with the new software coming a week after the release of the fifth macOS Monterey 12.3 beta. The RC represents the final version of macOS Monterey 12.3 that will be released publicly next week.

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.

macOS 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.

There are also new emoji characters, including melting face, biting lip, heart hands, bubbles, beans, face with diagonal mouth, palm up hand, eggs, troll, low battery, coral, lotus, and more.

Update: The update is now also available to public beta testers.

Related Forum: macOS Monterey

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Top Rated Comments

Realityck Avatar
53 months ago
For macOS 12.3 RC (21E230) - March 8, 2022
[SPOILER="macOS Monterey 12.3 Release Notes"]
[HEADING=2]Apple Pay[/HEADING]
[HEADING=3]New Features[/HEADING]

* Developers can express payment network preference in PKPaymentRequest ('https://developer.apple.com/documentation/passkit/pkpaymentrequest'). Network preference is determined by the order of supportedNetworks ('https://developer.apple.com/documentation/passkit/pkpaymentrequest/1619329-supportednetworks'). This won’t override the user’s default card selection, but if the card is multi-SSD, then the network preference order determines which SSD is selected. (80827905)

[HEADING=2]Authentication[/HEADING]
[HEADING=3]New Features[/HEADING]

* Support is added to the passkey technology preview, enabling signing in to passkey-compatible websites and apps on Mac and iPad using an iPhone with a saved passkey. (87998252)

[HEADING=2]Game Controller[/HEADING]
[HEADING=3]New Features[/HEADING]

* Support is now available for new DualSense adaptive trigger firmware features available via GCDualSenseAdaptiveTrigger ('https://developer.apple.com/documentation/gamecontroller/gcdualsenseadaptivetrigger'). (87433163)

[HEADING=2]iWork[/HEADING]
[HEADING=3]Known Issues[/HEADING]

* Collaboration scenarios might not work when the user configures the system to a right-to-left language. (89078453)
Workaround: Use iWork.com ('https://developer.apple.com/documentation/iWork.com') to collaborate in Safari using a right-to-left language.

[HEADING=2]Kernel[/HEADING]
[HEADING=3]Deprecations[/HEADING]

* 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)

[HEADING=2]libc++[/HEADING]
[HEADING=3]New Features[/HEADING]

* The following new C++20 and C++23 features are now implemented:

* C++20 library concepts defined in <concepts>.
* constexpr for std::swap() and swap-related functions.
* Miscellaneous constexpr-ification in the library.
* std::atomic now default initializes as expected.
* A .contains() method for associative containers.
* Added std::bind_front(). (88131816)


[HEADING=3]Deprecations[/HEADING]

* Some extensions in std::tuple were removed to fix bugs caused by those extensions:

* Tuples can no longer be constructed from fewer than the number of elements in the tuple. Previously, elements that weren’t specified were default-constructed; now this is a compiler error.
* A tuple can no longer be constructed from an array.
* The std::result_of and std::is_literal_type type traits are no longer available in C++20 mode, as specified in the Standard.


[HEADING=2]Python[/HEADING]
[HEADING=3]Deprecations[/HEADING]

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

[HEADING=2]StoreKit[/HEADING]
[HEADING=3]New Features[/HEADING]

* SKTestSession ('https://developer.apple.com/documentation/storekittest/sktestsession') has three new methods to simulate a subscription requiring price increase consent, simulate consenting to a pending price increase, and simulate declining a price increase in automated tests. (84556183)
* SKTestSession has two new Boolean properties to simulate billing retry and grace period in automated tests. You can identify and simulate the resolution of billing retry issues using the same APIs as interrupted purchases. (83956205)
* Users can now test the billing retry and grace period states using StoreKit Testing in Xcode. Use Xcode 13.3 or later to enable billing retry testing and toggle whether the app offers a grace period. Use isInBillingRetry ('https://developer.apple.com/documentation/storekit/product/subscriptioninfo/renewalinfo/3749502-isinbillingretry') and gracePeriodExpirationDate ('https://developer.apple.com/documentation/storekit/product/subscriptioninfo/renewalinfo/3749500-graceperiodexpirationdate') to handle these states in the app. (83938270)
* StoreKit error types now conform to LocalizedError ('https://developer.apple.com/documentation/foundation/localizederror'). (78735204)
* Users can test subscription price increase behavior using StoreKit Testing in Xcode. Use Xcode 13.3 or later to set a price increase, then use paymentQueueShouldShowPriceConsent(_:) ('https://developer.apple.com/documentation/storekit/skpaymentqueuedelegate/3521328-paymentqueueshouldshowpriceconse'), showPriceConsentIfNeeded() ('https://developer.apple.com/documentation/storekit/skpaymentqueue/3521327-showpriceconsentifneeded'), and priceIncreaseStatus ('https://developer.apple.com/documentation/storekit/product/subscriptioninfo/renewalinfo/3822292-priceincreasestatus') in the app. (58770817)
* Some types in StoreKit now have a localizedDescription read-only Stringinstance property. This property can be used to get a human-readable description of the value, localized for the device’s current locale. These types include: Product.ProductType ('https://developer.apple.com/documentation/storekit/product/producttype'), Product.SubscriptionInfo.RenewalState ('https://developer.apple.com/documentation/storekit/product/subscriptioninfo/renewalstate'), expirationReason ('https://developer.apple.com/documentation/storekit/product/subscriptioninfo/renewalinfo/3749499-expirationreason'), priceIncreaseStatus ('https://developer.apple.com/documentation/storekit/product/subscriptioninfo/renewalinfo/3822292-priceincreasestatus'), Transaction.OfferType ('https://developer.apple.com/documentation/storekit/transaction/offertype'), Product.SubscriptionOffer.OfferType ('https://developer.apple.com/documentation/storekit/product/subscriptionoffer/offertype'), Product.SubscriptionOffer.PaymentMode ('https://developer.apple.com/documentation/storekit/product/subscriptionoffer/paymentmode'), Product.SubscriptionPeriod.Unit ('https://developer.apple.com/documentation/storekit/product/subscriptionperiod/unit'), Transaction.RevocationReason ('https://developer.apple.com/documentation/storekit/transaction/revocationreason'), and Transaction.OwnershipType ('https://developer.apple.com/documentation/storekit/transaction/ownershiptype'). (78735060)

[HEADING=2]Universal Control[/HEADING]
[HEADING=3]Known Issues[/HEADING]

* 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)

[HEADING=2]WebKit[/HEADING]
[HEADING=3]Deprecations[/HEADING]

* Support for inline viewing of PostScript files is no longer available. (88172449)

[/SPOILER]
Score: 5 Votes (Like | Disagree)
fhall1 Avatar
53 months ago
Wow - only 8 comments after almost 24 hours?!? I figured there would be lots of reporting on bugs finally fixed/still not fixed, etc.
Score: 3 Votes (Like | Disagree)
Heindijs Avatar
53 months ago
I'm not even exited for Universal Control, I'm just glad that 12.3 fixes the artifacts on the sides of transparent windows such as control centre when running it on a Mac with certain Intel HD graphics chips...
Score: 3 Votes (Like | Disagree)
53 months ago
6800/6900XT GPU performance issues persist. :(
Score: 2 Votes (Like | Disagree)
53 months ago

I thought I was going crazy and it was still only me.
It's definitely related to APFS - I have one HPFS+ volume that mounts instantly. Something major changed in how they handle the file system. It wouldn't be bad if it would mount them all at the same time, but it's sequential, so is a major PITA. Like booting circa 2002.
Score: 1 Votes (Like | Disagree)
53 months ago
And it *STILL* hasn't fixed the mounting delays for external USB drives. 30-60 second per drive.
Score: 1 Votes (Like | Disagree)