Apple’s most meaningful communication about this inexcusable failure of support were the 404 errors from its download pages.
certificates
Validating signatures isn’t straightforward. GUI apps are limited, and command tools confusing and prone to user error.
Don’t rely on being able to use any Apple installer package unless it has been downloaded recently: its certificate is about to expire.
As feared, the studentd daemon and its mysterious certificate have reappeared, and are now set to remain in Mojave in perpetuity.
If you’ve updated to macOS 10.14.4, you’ve already installed supporting software to use your Mac in a classroom. Was this an error in the update? What does it do?
Have you updated to 10.14.4? Checked your login keychain? You may see a new security certificate there. What’s it for?
Can you sign AppleScript apps in Script Editor? Is there a better tool? What’s the best way to sign a command tool developed in Xcode?
One important requirement for code signatures is with Mojave’s new privacy controls. Are they needed, though?
Testing at the command line, with What’s Your Sign?, and according to the requirements of the signature.
How to perform ad hoc signing, signing with a personal certificate, and set signing up in Xcode.
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