Apple Releases watchOS 6.2.1 and macOS 10.15.4 Supplemental Update

Member of the AppleVis Editorial Team

Apple has today released watchOS 6.2.1 and a supplemental update to macOS 10.15.4, addressing an issue that prevented Macs running macOS 10.15.4 and Apple Watches running watchOS 6.2 from participating in FaceTime calls with devices running iOS 9.3.6 or earlier, or OS X El Capitan 10.11.6 or earlier.

According to Apple's release notes for watchOS 6.2.1, via 9to5Mac the update:

  • Fixes an issue where devices running watchOS 6.2 could not participate in FaceTime audio calls with devices running iOS 9.3.6 and earlier or OS X El Capitan 10.11.6 and earlier.

According to Apple's release notes for macOS Catalina Supplemental Update, via MacRumors the update fixes the aforementioned issue with FaceTime, as well as issues with Office 365 accounts, the 2020 MacBook Air, and USB-C.

‌macOS Catalina‌ 10.15.4 supplemental update improves the stability and security of your Mac.

  • Fixes an issue where Mac computers running ‌macOS Catalina‌ 10.15.4 could not participate in ‌FaceTime‌ calls with devices running iOS 9.3.6 and earlier or OS X El Capitan 10.11.6 and earlier
  • Resolves an issue where you may repeatedly receive a password prompt for an Office 365 account
  • Fixes an issue where ‌MacBook Air‌ (Retina, 13-inch, 2020) may hang in Setup Assistant or when disconnecting and reconnecting a 4K or 5K external display
  • Resolves an issue where a USB-C port in your Mac may become unresponsive.

As these are minor updates released to address a handful of specific issues, our expectation is that they do not contain any accessibility changes for blind and low-vision users. However, if you do notice any changes, improvements or regressions in your use of these releases, please let us know by posting a comment below.

How to update

watchOS 6.2.1 is available via Over-the-Air Update (Settings > General > Software Update) or by going to the Watch app on your iPhone and navigating to General> Software Update. To install the update, your Watch must be connected to its charger and have at least 50% battery power.

macOS Catalina 10.15.4 Supplemental Update can be downloaded by going to System Preferences > Software Update.

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Submitted by PaulMartz on Friday, April 10, 2020

Member of the AppleVis Blog Team

I previously noted that 10.15.3 would crash on wake only if the Messages app were running. I upgraded to 10.15.4 hoping for a fix. That turned out to be a mistake. After the upgrade, my system has crashed on wake 3 out of 4 times, irrespective of the Messages app.

As no one else seems to be experiencing this problem, I suspect it must be my system. It's a mid-2012 MacBook Pro with the OS installed on an external SSD.

I cleared the NVRAM by rebooting with Command+Option+P+R. This changed my startup disk to the default hard drive, which I needed to manually change back to the external SSD. Since clearing the NVRAM, I've slept the computer multiple times with no crashes, knock on wood.