Apple Seeds Second Beta of Upcoming macOS Catalina 10.15.3 Update to Developers [Update: Public Beta Available] - MacRumorsOpen MenuShow RoundupsShow Forums menuVisit ForumsOpen Sidebar
Skip to Content

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

by

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
83 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
83 months ago
So glad I am skipping Catalina. What an embarrassment.
Score: 4 Votes (Like | Disagree)
orbital~debris Avatar
83 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)
83 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)
83 months ago
Do iMacs sleep now?
Score: 3 Votes (Like | Disagree)
83 months 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!

Attachment Image
Score: 2 Votes (Like | Disagree)

Popular Stories

HomePod mini and Apple TV Sage

New Apple TV and HomePod Mini Are 'Nearly Ready' to Launch, New Siri Remote Also Rumored

Sunday May 31, 2026 8:47 am PDT by
New models of the Apple TV 4K and HomePod mini are "nearly ready to go," according to the latest word from Bloomberg's Mark Gurman. Subscribe to the MacRumors YouTube channel for more videos. Both devices have been ready "for months," but Apple is holding off on launching them until the more personalized version of Siri is available, he said. "I am told the hardware for the next Apple TV...
Apple Foldable Thumb

First 'Confirmed' iPhone Ultra Color Allegedly Revealed in Leaked Image

Monday June 1, 2026 4:39 am PDT by
Apple is expected to launch its first foldable iPhone later this year. Rumors suggest the "iPhone Ultra" will come in two color options, and a leaker shared an image today that allegedly shows one of them. Posted on Weibo by the Chinese leaker known as Ice Universe, the image purportedly offers a first glimpse of Apple's foldable in white. The device is believed to have entered early mass...
Meta Ray Ban Glasses

Apple Glasses Reportedly Launching in 'Late 2027' With These Features

Sunday May 31, 2026 9:21 am PDT by
Apple is now aiming to release its first smart glasses in "late 2027," according to the latest word from Bloomberg's Mark Gurman. Meta Ray-Bans He previously said that Apple planned to begin shipping the glasses by early 2027, but he said the product has faced development delays. The glasses will feature "oval-shaped cameras, unique colors, and multiple frame styles," according to Gurman....

🔗 Related Apple News & Rumors

Stay updated with the latest Apple ecosystem news and verified rumors