Last Week on My Mac: Surprise Supplemental Update

Supplemental Updates aren’t that unusual now, but last week’s came as a real surprise. It was released just fifteen days after the 10.15.4 update, quicker than some major security patches. Yet it wasn’t to rectify a glaring vulnerability or a spate of kernel panics: its big reason was to fix an incompatibility with FaceTime in older versions of iOS.

Apple had pulled out all the stops and built a Supplemental Update for Catalina because of problems connecting FaceTime with devices running older versions of iOS.

Weigh each word in that sentence. Here was Apple moving heaven and earth to ensure that Mac users could still enjoy FaceTime connections with iPhones and iPads still not running the current release of iOS/iPadOS. It was a problem which few of us, who had already updated our sleek modern devices to iOS 13.4.1, had even noticed. But with so many Mac and iOS users around the world now relying on FaceTime to keep in touch with friends, colleagues and relatives, Apple made this fix as important as the most dangerous of security vulnerabilities.

There were two further highly unusual features about this update. For the first time in many years, Apple’s release notes are complete and comprehensive. Having scoured my system to detect any changes beyond the four which Apple detailed, I’ve drawn a blank. Despite the speed with which it was released, Apple took the trouble to tell us in full exactly what changes the update brought.

Given the very limited nature of its fixes, you might then wonder why the update was over one gigabyte in size: the answer is, of course, because it contains a complete set of firmware updates for each supported model of Mac, even though none of those regular firmware updates has changed since the 10.15.4 update. Users of iMac17,1 models who are still stuck with firmware which is dangerously out of date have, in the main, been disappointed that even this Supplemental Update hasn’t brought their iMacs any relief. Maybe next time their patience will be rewarded.

Unusually, for logistic reasons, I updated my T2-equipped iMac Pro here using the standalone installer, which brings me to the third highly unusual feature of this update: it’s the first time that, during a macOS update, this iMac Pro has shut down completely and required a manual startup to finish the installation. This was followed by a long period between logging back in and starting the Finder, during which a progress spinner just spun and spun. Right up to the very end of the update process, I had great doubt that my iMac Pro was going to survive it unscathed.

I shouldn’t be comparing macOS system updates to fairground rides, but they’re getting increasingly like the traditional Ghost Train (Dark Ride), not a rollercoaster. In the latter, you can see what’s coming, which is all part of the experience. Your car reaches the apex of the track and you look down and scream. In a Ghost Train you never know what’s going to happen next: one minute everything’s gone black, then all hell breaks loose, just like a T2 installing a macOS update.

Those whose Macs have T2 chips are by now quite used to their computer playing dead during an update. When my iMac’s screen went black and it seemed to stop dead, I presumed it was just another of those moments. Five minutes passed, then ten. I was actually scared to start it up, being well aware of those T2 Macs that have been bricked through failed or incomplete firmware updates. After fifteen minutes I tentatively touched the Power button – being sure that I didn’t hold it long enough to risk forcing a restart.

I breathed a great sigh of relief when it started up and went straight back into installing the update again. I logged back in, and expected the Finder to appear any second. All I then got was a progress spinner on the login screen, as if it had hung in the last few yards of this update marathon, too dead beat to cross the finishing line. By that stage I had to go out, but when I returned it all looked fine. I was finally out of my trip in the macOS update Ghost Train.

I understand the practical difficulties of providing informative messages during system updates like this, particularly for an urgent patch which must have been put together in just a few days. But why can’t Apple at least inform us of the likely sequence which our Macs should follow during each update? Had I been warned that, at some stage, my Mac was likely to shut down and would need to be started up again, I would have been better prepared and less stressed. A rough estimate of the likely time taken would also help me plan when I can apply an update.

For future updates, I’ll try to describe here what the process entails so that you at least have a better idea of what will take place when you update. But it would be really considerate of Apple to do this for us. After all, it should know, so why can’t it communicate?