Apple Seeds Third Beta of Upcoming macOS Catalina 10.15.3 Update to Developers

Apple today seeded the third beta of an upcoming macOS 10.15.3 update to developers for testing purposes, one week after seeding the second beta and more than 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 major new changes in the first two betas of macOS Catalina 10.15.3, but we'll update this post if there's anything new in the third beta.

Related Forum: macOS Catalina

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Top Rated Comments

AppleMatt Avatar
69 months ago
Good news with this update:

https://forums.macrumors.com/threads/psa-apple-mail-bugs-can-lead-to-data-loss-in-macos-catalina.2205346/post-28158834

Attachment Image
Score: 11 Votes (Like | Disagree)
ruslansv Avatar
69 months ago

And once again is the most important question: Has Apple finally fixed the Mail data loss bug?
Why does Apple stubbornly refuse to list what is fixed and what is not fixed (or targeted to a different release) via proper release notes (and not a joke of release notes they're providing)?
Score: 10 Votes (Like | Disagree)
macdos Avatar
69 months ago
It would be insanely great if Apple devotes some effort to maximize performance and minimize memory consumption. We should not have to rely on Macfanscontrol and Lingon to control fan speed and disable unncessary daemons, it should be builtin, as in Windows.
Score: 6 Votes (Like | Disagree)
grandchester Avatar
69 months ago
Hope it fixes the iCloud verification finally. Real tired of entering iCloud and Mac passwords AND the code on my iPhone for some reason every other day.
Score: 5 Votes (Like | Disagree)
sugargliderdude Avatar
69 months ago
think I'm going to install Catalina 10.15.3 once its released to the public
Score: 4 Votes (Like | Disagree)
bsbeamer Avatar
69 months ago
Really hope this release fixes the AMD 5XXX series drivers for MBP16,1 5500M and RX 5700 & RX 5700 XT in eGPU. Every video software vendor is pointing to those drivers as the reason for METAL issues with their software that disappear with RX580 or go software only.
Score: 4 Votes (Like | Disagree)