Disabling macOS Beta Updates
There’s a good reason why I don’t want the betas installed on that Mac: it’s the one that runs the version of macOS that most of my customers will be using. It’s also the machine that submits products to the App Store, and we all know how picky they can be about tool and OS versions.
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To turn off beta updates I first quit the App Store app and checked that there was a beta seed URL for Software Update using the Terminal[…] I then nuked it:
$ sudo defaults delete /Library/Preferences/com.apple.SoftwareUpdate CatalogURL
