Apple Seeds Second Beta of Upcoming macOS Catalina 10.15.3 Update to Developers [Update: Public Beta Available]

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.


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 Roundup: macOS Catalina

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1 week ago
Hopefully the delay is because Apple have focussed on eliminating the email data loss bug(s).
Still waiting to upgrade to Catalina…
Rating: 6 Votes
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1 week ago
So glad I am skipping Catalina. What an embarrassment.
Rating: 4 Votes
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1 week 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.
Rating: 3 Votes
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1 week ago
Do iMacs sleep now?
Rating: 3 Votes
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1 week 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.)
Rating: 3 Votes
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1 week ago


10.16 betas will be here within 5 months.


So we can get new bugs in addition to all of the existing ones
Rating: 2 Votes
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1 week ago
Is keychain bug fixed for Macs bound to AD with mobile accounts and FileVault on?
Rating: 2 Votes
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1 week ago
Here's an interesting change... They made the Mac's Display in the "Display" system preference have a text window open titled "Think Different" and the text is of the Think Different mantra. Nice Apple!

Rating: 2 Votes
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1 week ago
Here's hoping they bring back the old iTunes Movie Store in the TV app. The new built-in store is a horrible user experience.
Rating: 2 Votes
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1 week ago
If you have more than 1 user account on your Mac, is the iCloud bug finally fixed that requires constant re-entering of my password when the primary user logs on?

It's infuriating.
Rating: 2 Votes
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