Apple has changed its instructions for resetting/repairing permissions on your Home folder, and important cure for many problems.
Disk Utility
Why you should always protect backup storage with a UPS. Should you also rebuild its directories every month? And when to archive rather than back up.
The Finder, Disk Utility and Terminal show disks and volumes differently, according to their function. This can appear confusing in Catalina until it has been explained.
When you go to perform a clean re-install of Catalina, what should you do? Which volume(s) to erase or delete, and how to fix problems?
What if you don’t want whole disk encryption? If your Mac doesn’t have T2, or if you’re using an external drive, encryption is still performed in software. Here’s a good solution.
Start up in Safe Mode: should it start by checking and repairing your boot disk, or should you do that separately in Recovery Mode?
Third party tools for checking and repairing APFS are still very limited. Is it better to use fsck to check and repair APFS?
Don’t just hold Command-R and hope that you’ll install the right version of macOS. Here’s structured decision-making to save you time.
Single-user mode to run fsck to check and repair your boot disk became tricky with Fusion Drives. With a T2 chip, it’s not practical in its traditional form.
It may be over 2 years old, but its supporting tools are more like those of a beta. Adding containers isn’t at all straightforward.
The Eclectic Light Company 