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iOS 13.6.1, iPadOS 13.6.1, and macOS 10.15.6 Supplemental Update Stomp Bugs

As the dog days of summer drag on, Apple has shipped three bug-fix operating system releases: iOS 13.6.1, iPadOS 13.6.1, and macOS 10.15.6 Supplemental Update.

iOS 13.6.1 and iPadOS 13.6.1

Apple released iOS 13.6.1 and iPadOS 13.6.1 to fix what could be a troubling issue in those operating systems. Both address “an issue where unneeded system data files might not be automatically deleted when available storage is low.” So if you are already running iOS 13.6 or iPadOS 13.6, you should probably update right away, especially if you’re mysteriously running out of storage space (see “iOS 13.6, iPadOS 13.6, macOS 10.15.6, watchOS 6.2.8, and tvOS 13.4.8 Add News Features, Car Keys, Symptom Tracking,” 15 July 2020).

iOS 13.6.1 release notes

Additionally, iOS 13.6.1 fixes:

  • A thermal management issue that caused some displays to exhibit a green tint. I’ve seen this on the iOS 14 beta.
  • A bug that could cause Exposure Notifications to be disabled for some users.

You can install these updates from Settings > General > Software Update, in iTunes, or in the Finder on Macs running macOS 10.15 Catalina or later. iOS 13.6.1 is a 109.4 MB download on the iPhone 11, and iPadOS 13.6.1 is an 81 MB download on a 10.5-inch iPad Pro.

Neither update has any published CVE security notes.

macOS Catalina 10.15.6 Supplemental Update

The macOS Catalina 10.15.6 Supplemental Update, which you can install from System Preferences > Software Update, fixes two bugs:

  • Instability when running virtualization apps like Parallels Desktop, VirtualBox, and VMWare Fusion
  • 2020 27-inch iMac screens appearing washed out after waking from sleep

macOS 10.15.6 release notes

At his Eclectic Light Company blog, Howard Oakley notes that only the Books and VoiceOver Utility apps saw small build number increments, although there were additional system-level files with changes. He suggests that the changes to the AMDRadeon kernel extensions may have addressed some kernel panic problems that a few users had been reporting after the macOS 10.15.6 update. Also notable is that Macs with Apple’s T2 chip receive new firmware, which you’ll remember can be installed only by Apple’s installer during a macOS update.

Again, there were no published security fixes.

If you’re already running 10.15.6 Catalina, particularly on a 2020 27-inch iMac, we recommend updating as soon as possible. Otherwise, feel free to wait a bit and see if other issues develop.

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Comments About iOS 13.6.1, iPadOS 13.6.1, and macOS 10.15.6 Supplemental Update Stomp Bugs

Notable Replies

  1. Always wait before updating to something of the form ?.?.0.

  2. Except when x.x.0 is close to being replaced by x+1.0.0. I wait a year before updating iOS on my iDevices so I just replaced iOS 12.x.x on my iPhone with iOS 13.6.0 couple of days ago and went to 13.6.1 today.

  3. and possibly introduced some new ones… :flushed:

    When I return to my office desk and plug in the external portrait display, MacOS now forgets that the orientation is rotated 90 degrees. Drives me nuts! Was fine before.

    On the plus side, my rotated mouse skills are getting better!


  4. I have not been offered either of the 13.6.1 updates. I always keep my devices up-to-date.

    I don’t think there is any reason to hesitate to install incremental updates. You could say, “But it might have bugs!” Sure, it might, but it is almost certainly being released to fix bugs you are living with! And an x.x.? update is very unlikely to have any major new features. It’s mostly likely just fixing bugs.

  5. In my experience as of late I’m afraid I have rarely encountered these x.x.x updates fix any bugs I’ve encountered (and reported), but they do sometimes introduce new bugs and more importantly they sometimes take forever to install. This latest mini Catalina update ended up blocking my Mac for about an hour. I know it had new T2 firmware to install and bla bla. But for Pete’s sake, it’s 2020 and this is on a $3k MBP, the fastest 13" Mac Apple has, equipped with a huge and super fast SSD and loads of fast RAM, and yet, a simple update that doesn’t really do anything for me (visible that is, not saying there’s no security benefit) ended up taking FOREVER. And not because of the download. Although the update was a bloated 3+GB, download over fiber was super fast. No, it’s the actual update that takes ages. This wasn’t always the case (especially not in combination with the lack of proper feedback on what’s going on) and not at all what I’d consider “progress” —in any sense of the word. And if this is indeed the very best Apple can do under the circumstances, well then maybe it’s time for a new macOS.

  6. I always view it as a good thing when a bug fix update fixes bugs that I have not yet encountered!

  7. Agreed, that it is. But it still doesn’t relieve from the frustration that results after going through countless updates only to see several long before discussed and reported bugs stubbornly remain unfixed.

  8. Just to note, my new iMac came with 10.15.6 and I hadn’t gotten around to installing the Supplemental Update for the first few days. Then it kernel panicked last night and when I Googled on the first line in the panic report, I discovered that it was exactly the thing that Howard Oakley was talking about as being fixed in the Supplemental Update.

    So yeah, there are bugs and some of them do get fixed and updating is worthwhile, even if you don’t notice the benefit immediately.

  9. Actually, ALL updates have bugs!

  10. All software has bugs. The hope is that the update fixes more than than it introduces, something that developers take seriously, as @das explains in

  11. As I was taught, a long time ago,

    1. All non-trivial programs have at least one bug.
    2. It is a sufficient condition for program triviality that it have no bugs.


  12. Apple never offered me iOS and iPadOS 13.6.1, but Apple did offer me iOS and iPadOS 13.7 and I promptly installed them. So far, no problems.

  13. iOS and iPadOS 13.7 aren’t out yet, so if you’re being offered them, you have a developer profile installed for getting betas.

  14. I wish Apple would label iOS betas as “betas.”

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