Apple Releases macOS Catalina 10.15.6 Supplemental Update With Virtualization Bug Fix

Apple today released a supplemental update for macOS Catalina 10.15.6, with the update coming a month after the original launch of macOS Catalina 10.15.6.

macos catalina wallpaper
The ‌‌macOS Catalina‌‌ 10.15.6 Supplemental Update can be downloaded from the Mac App Store using the Update feature in the System Preferences app.

According to Apple's release notes, the update fixes a problem that could cause virtualization apps like VMware to crash. It also fixes an issue that could cause the 2020 iMac to appear washed out after waking from sleep. Apple's full release notes are below:

macOS Catalina 10.15.6 supplemental update includes bug fixes for your Mac.

- Fixes a stability issue that could occur when running virtualization apps
- Resolves an issue where an iMac (Retina 5K, 27-inch, 2020) may appear washed out after waking from sleep

macOS Catalina 10.15.6 will likely be the last update to the macOS Catalina operating system as Apple transitions to macOS Big Sur, the newest version of macOS set to be released in the fall.

Related Forum: macOS Catalina

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Top Rated Comments

ignatius345 Avatar
64 months ago

A fired Apple employee will not starve. I don't demand perfection from my family because they don't work for Apple as professionally paid software people. Somebody failed and is responsible that there was field exposure. Apple got lucky that this wasn't a data corruption bug.

OS development is only as complex as what you develop. What they are changing in a point release this late in the development cycle should be fixing bugs and thoroughly testing them. The general expectation of incremental point releases is that the higher the number the less changes involved. That small amount of change should be thoroughly tested, especially if it's to such core service as the HV FW.

Somebody fsck'd up big time. Heads have to roll.
Jesus. Give it a rest. Both of you. Nobody cares. I’m reading through this thread trying to find salient info about bug fixes, not listen to your rants about whether people should be fired or not. Hopefully a moderator will come in and delete all of these (and this message as well). Thank you.
Score: 23 Votes (Like | Disagree)
Colonel Blimp Avatar
64 months ago

Somebody fsck'd up big time. Heads have to roll.
Whose heads? The programmer who wrote the code? An individual software tester who failed to catch the bug? The person who wrote the test plan? The QA manager who supervised the testing? The QA director?

How about the Product Manager who signed off on the release? The director of software engineering? The VP of Software?

Or how about the executives who decided to allocate only so many resources to software testing, while maintaining pressure to meet an ambitious feature release schedule?

In any company, the responsibility for releasing buggy software goes all the way up the chain, not just theoretically but in actual practice. The danger of demanding that heads roll is that 1) the heads probably won’t belong to the people responsible for creating the conditions that lead to the release of buggy software, 2) the people who replace your decapitated developers will have less experience with the software you’re developing, and 3) your developers may become more concerned about covering their posteriors (a singularly inappropriate metaphor for someone facing decapitation) than about working together to release high-quality software.

Don’t get me wrong. As someone who used to run software QA for a living, I’m inclined to think that people should be serving jail time for some of the software bugs I keep reading about, but actually deciding who to fire or hang or sacrifice to the Red God isn’t entirely straightforward, nor perhaps entirely helpful.
Score: 13 Votes (Like | Disagree)
chucker23n1 Avatar
64 months ago
So, about two and a half weeks between VMware narrowing it down to a sandbox issue, reporting it to Apple, and Apple releasing a fix. That's not so bad.
Score: 11 Votes (Like | Disagree)
CJ Dorschel Avatar
64 months ago
I've been a Mac user for almost 20 years yet this is the first time I have never updated my systems to the latest OS. I've held off on 10.15 but am considering updating as Apple has begun to drop support for certain aspects of 10.14 (security updates, etc will continue of course). I've been experiencing issues on two Mac Pro's that haven't been resolved with weeks of online research, clean installs, and Apple tech leading me to consider updating to 10.15.

My biggest concern is access to root as Apple continues to extend SIP. I've always disabled SIP and Gatekeeper as I require read/write access for development and third party apps. Certainly this it not something everyone should do and doing so is always with risk yet is a necessity for my personal needs and I utilize other precautions, etc.

That stated, my biggest concern is read/write access to root as Apple created two volumes for Applications - User and System. I've created a script that mounts the drive for read/write, assigns the necessary permissions, then deletes it. I've used this on my MacBook Pro for development work which is now running Big Sur.

My concerns with 10.15:

- Will this be necessary in case my system needs to be restarted? (I rarely do so unless necessary)
- Has Apple locked the ability to mount and change root permissions with incremental 10.15.x updates?

Don't even get me started on Big Sur. Running it on my MacBook Pro for development and struggling to adjust to the UI in addition to SSV. I completely understand Apple's focus on security especially for novices/everyday users, yet their focus on locking the system down further with each release makes it difficult for third party developers to maintain their apps which is most likely Apple's true intentions as they want to force developers to utilize the Mac App Store. Given there are ways to easily bypass Apple's security measures - granted they've made the processes more difficult - and users have already found backdoors in Big Sur, I wonder if there are better methods for security measures than what Apple has been implementing since SIP and Gatekeeper were introduced.
Score: 10 Votes (Like | Disagree)
jchap Avatar
64 months ago

Hope somebody lost their job.
It seems a bit cruel to wish that someone would lose their job (accompanied with all the resulting hardship) over this. It must have been an inconvenience to you and to many other people to deal with this bug, but is it reasonable to attribute the problem to one person in specific, or to make one person take the blame for something Apple might not have known about or fully understood the implications of to begin with? Do you also expect this same level of perfection from your friends, your family and those you deal with in everyday life?

Make no mistake—I, too, get upset and irritated when software bugs interrupt my productivity and enjoyment of technology. I’ve complained a lot to Apple over the years, and logged countless support cases for numerous products, both software and hardware. When something is not to my liking or when it causes me inconvenience as a user, I will complain.

That said, I also realize that with something as complex as an operating system, there’s not just one person pulling the strings behind the curtain, so to speak. It’s a team effort, and sometimes mistakes are made. No manufacturer has ever released a flawless product without blemish, one which operates perfectly in every way. In the end, it’s up to the end user to make sure their bases are covered, so that when a particular piece of software or hardware they use does not function properly, they have a means of recovering.
Score: 8 Votes (Like | Disagree)
Belle Pomme Avatar
64 months ago
My MacBook Pro also has that washed-out problem too, so I hope it helps.
Score: 7 Votes (Like | Disagree)