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
orbital~debris
76 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
BWhaler
76 months ago
So glad I am skipping Catalina. What an embarrassment.
Score: 4 Votes (Like | Disagree)
globalmatt Avatar
globalmatt
76 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
Mightee
76 months ago
Do iMacs sleep now?
Score: 3 Votes (Like | Disagree)
orbital~debris Avatar
orbital~debris
76 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
ruslansv
76 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)
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