Apple today seeded the second beta of an upcoming macOS 10.15.3 update to developers for testing purposes, nearly a month after seeding the first beta and over a month after releasing the macOS Catalina 10.15.2 update.

The new ‌‌macOS Catalina‌‌ beta can be downloaded using the Software Update mechanism in System Preferences after installing the proper software from the Developer Center.

macos catalina wallpaper
We don't yet know what improvements the third update to macOS Catalina will bring, but it will likely focus on performance improvements, security updates, and fixes for bugs that weren't able to be fixed in the macOS Catalina 10.15.2 update.

macOS Catalina 10.15.3 has code in it that suggests a new "Pro Mode" is coming to Apple's Macs. Pro Mode appears to be an optional setting that overrides fan speed limits and energy saving restrictions to improve performance. The code says that apps "may run faster" but battery life could decrease and fan noise could increase.

It's not entirely clear if Pro Mode is coming to Macs in the 10.15.3 release, but the code is there so it is a possibility.

We didn't find any other new changes in the first beta of macOS Catalina 10.15.3, but we'll update this post if there's anything new in the second beta.

Related Forum: macOS Catalina

Top Rated Comments

orbital~debris Avatar
48 months ago
Hopefully the delay is because Apple have focussed on eliminating the email data loss bug(s).
Still waiting to upgrade to Catalina…
Score: 6 Votes (Like | Disagree)
BWhaler Avatar
48 months ago
So glad I am skipping Catalina. What an embarrassment.
Score: 4 Votes (Like | Disagree)
globalmatt Avatar
48 months ago

Hopefully the delay is because Apple have focussed on eliminating the email data loss bug(s).
Still waiting to upgrade to Catalina…
I’m really hoping this too. Currently using Thunderbird on Catalina for this reason. It’s not as nice to use as Apple Mail, but at least it doesn’t silently delete my emails.
Score: 3 Votes (Like | Disagree)
Mightee Avatar
48 months ago
Do iMacs sleep now?
Score: 3 Votes (Like | Disagree)
orbital~debris Avatar
48 months ago

MR can you please combine your “Apple Seeds Beta X” news stories for all the devices?

Your front page with a wall of these for each product is a bit silly.
Hmm… do you see them all on the front page?

I was going to comment that I'd like to see the macOS (and watchOS & tvOS) beta news items in the main column instead of the 'Page 2' sidebar. Especially the macOS ones, since this is MacRumours, after all.

Separating them is good, as it allows a relevant discussion thread per news item. (And that would be another reason to have the macOS item appear in the main page - it might generate more views and more comments in the linked thread.)
Score: 3 Votes (Like | Disagree)
ruslansv Avatar
48 months ago

10.16 betas will be here within 5 months.
So we can get new bugs in addition to all of the existing ones
Score: 2 Votes (Like | Disagree)

Popular Stories

iOS 17

Apple Releases iOS 17.0.1 and iPadOS 17.0.1 With Bug Fixes, Plus iOS 17.0.2 for iPhone 15 Models

Thursday September 21, 2023 10:28 am PDT by
Apple today released iOS 17.0.1 and iPadOS 17.0.1 updates for the iPhone and the iPad, adding bug fixes to the new software. The iOS 17.0.1 and iPadOS 17.0.1 updates come just a few days after Apple launched iOS 17 and iPadOS 17. The software, which is build 21A340, can be downloaded on eligible iPhones and iPads over-the-air by going to Settings > General > Software Update. There is a...
iPhone 16 Mock Header With Dynamic Island

Skipping the iPhone 15 Pro? Here's What's Rumored for iPhone 16 Pro

Friday September 22, 2023 9:29 am PDT by
Are you skipping the iPhone 15 Pro and waiting another year to upgrade? If so, we already have some iPhone 16 Pro rumors for you. Below, we recap new features rumored for the iPhone 16 Pro models so far:Larger displays: The iPhone 16 Pro and iPhone 16 Pro Max will be equipped with larger 6.3-inch and 6.9-inch displays, respectively, according to Ross Young, CEO of Display Supply Chain...
Update Your iPhone 15 to iOS 17

Warning: Update Your iPhone 15 to iOS 17.0.2 Before Transferring Data From Another iPhone

Friday September 22, 2023 6:36 am PDT by
If you are unboxing an iPhone 15, iPhone 15 Plus, iPhone 15 Pro, or iPhone 15 Pro Max today, make sure to update the device to iOS 17.0.2 before transferring data to the device from another iPhone, or else you might encounter issues. iOS 17.0.2 is only available for the iPhone 15 lineup. Apple says the update fixes an issue that may prevent transferring data directly from another iPhone...
Apple Watch Ultra 2 double tap gesture 230912

watchOS 10.1 to Enable Apple Watch's New 'Double Tap' Gesture

Thursday September 21, 2023 12:52 pm PDT by
The new Double Tap gesture for the Apple Watch Series 9 and the Apple Watch Ultra 2 will be enabled starting with watchOS 10.1, according to Marques Brownlee, host of the popular tech-focused YouTube channel MKBHD. The first beta of watchOS 10.1 will likely be available by next week, and Apple announced that the software update will be released next month. Brownlee shared his impressions...
emojipedia 15 1 emoji

Emoji Coming to Future iOS 17 Update Include Shaking Head, Brown Mushroom, Lime, Phoenix and More

Tuesday September 19, 2023 12:43 pm PDT by
As Apple was announcing new iPhone models last week, the Unicode Consortium was officially approving new emoji characters that are set to be added to smartphones starting in 2024. Mockup of new emoji from Emojipedia Approved Unicode 15.1 emoji include phoenix, lime, an edible mushroom, shaking head vertically (as in a "yes" nod), shaking head horizontally (a "no" head shake), and broken...
iPhone 15 Pro Fingerprints

Apple Says Fingerprints Can 'Temporarily Alter the Color' of iPhone 15 Pro's Titanium Frame

Thursday September 21, 2023 2:48 pm PDT by
In a support document updated today, Apple indicates that fingerprints might "temporarily alter the color" of the titanium frame on the iPhone 15 Pro and iPhone 15 Pro Max. Fortunately, Apple says this is not a permanent condition, as the fingerprints can be wiped off just like on any other iPhone to restore a clean finish. "For iPhone 15 Pro and iPhone 15 Pro Max, the oil from your skin...