Yikes! Macos 10.15, released in q4 2019, continues in Fall 2020 to have many unfixed, serious, well-known issues. And Beta versions of 10.16/11, due 2020-09 (Sept) have been buggy as well. Here are links and summaries about a few of those issues, like this analysis by a software engineer who worked at Apple for 18 years: https://tidbits.com/2019/10/21/six-reasons-why-ios-13-and-catalina-are-so-buggy/

Macos 10.15 aka catalina (and likely 10.16) slow by design

Sites below have deep-dive discussions about if/when safe to do macos updgrades, such as from 10.14 (mojave) to 10.15 (catalina).

But 10.15 (catalina) still has a overheating problem detailed in a thread started on Oct 8, 2019 and currently 23 pages long at MacBook Pro Overheating after Catalina (excerpt below)…

  • On High Sierra(10.13):Working temp is 44~48C, fans spin ~1200rpm, battery lasts about 7 hours (this is a mid-2013 model so i’d say the battery life is still quite decent, over 50% of the original battery life on a 7 year old machine)

  • On Mojave (10.14):Working temp 50~54C, fans spin ~1500rpm, battery lasts about 5 hours.

  • On Catalina (10.15) Working temp 60-62C, fans spin ~2000rpm, battery lasts about 4 hours. The overheating persists even after 6th update to 10.15.5 and with 10.16 in a few months may never get fixed.

Even if your catalina laptop is not overheating with result of battery not lasting long… Excerpts below detail yet anotherissue generally known as “slow-by-design”, just one of many serious issues causing folks to stay with 10.14 (aka Mojave). Slow by design

https://eclecticlight.co/2020/05/24/last-week-on-my-mac-nobbled-and-hobbled-by-notarization/

“The bigger story, though, started with Allan Odgaard’s article titled macOS 10.15: Slow by Design, in which he claims that every time a user runs a new script in Catalina, it’s checked to see whether it’s notarized, imposing a significant pause while that’s checked with Apple’s servers. This was further explored by Jeff Johnson, who concludes that Catalina does indeed check whether unsigned executable code, including shell scripts, has been notarized.”

So even if you write a one line shell script and run it in a terminal, you will get a delay!

You can test this by running the following two lines in a terminal:

echo $'#!/bin/sh\necho Hello' > /tmp/test.sh && chmod a+x /tmp/test.sh
time /tmp/test.sh && time /tmp/test.sh

Update 2020-05-23: Some users have a Developer Tools category in the Security & Privacy preferences pane (I don’t). If your terminal is added to this category, you will not be able to reproduce this delay.

Can’t hide macos upgrades. Compat guides…

IT folks now need new ways to prevent 10.14 end-users from inadvertently doing un-reversible 10.14 to 10.15/10.16 upgrade. Good summary of the issue and suggestions IT folks should make to apple to fix it https://babodee.wordpress.com/2020/04/16/apple-plans-on-removing-enterprise-options-for-macos-software-update/ A max deferral of 90-days for hiding major macos updates is coming! (I hope apple is not contemplating forced updates similar to win10!) For example, even/only for macs in MDM, “Once macOS 10.16 is live, you will be able to hide the Major (Upgrade) and Minor (Point Release) Updates for [a maximum of upto] 90 Days” per item 7 at: mrmacintosh.com 2020-003-update

Inability to hide already started for 10.14: since 2020-003 May 2020 update, 10.14 macs will no longer hide Catalina-badge reminders. Before 2020-003 “softwareupdate –ignore” would hide Catalina nagging, but with 2020-003 Apple deprecated it:

sudo softwareupdate --ignore "macOS Catalina"
Ignored updates:
(
    "macOS Catalina"
)
Ignoring software updates is deprecated.
The ability to ignore individual updates will be removed in a future release of macOS.

With more major changes under the hood in 10.16, like replacing kext with sext, expect breakage in compatibility guides for software on 10.16, especially for scientific software.

When 10.15 dropped, this blog started listing dozens of scientific apps ability run on catalina (macos 10.15.x): macinchem.org

Tho the majority are chemistry-related, there are more general-purpose apps as well, and some common work-arounds. The list has had 13 updates, most recently in Jan 2020, and by this time almost, but not all, apps now can run on 10.15, but some with reduced abilities like IgorPro that warns: “We do not consider any version of Igor Pro 8 to be fully supported on Catalina, though we will do our best to fix Catalina specific bugs.”

Anyone know of good similar sites that track compatability issues, and or offer work-arounds?

P.S. Some innovative ways to deal with shortcomings in newer macos(es) by running older versions of software…

Retroactive on github

“Run Aperture, iPhoto, and iTunes on macOS Catalina. Xcode 11.4.1 on macOS Mojave. Final Cut Pro 7, Logic Pro 9, and iWork ’09 on macOS Mojave or macOS High Sierra.” Uses swizzling!