When signed out of iCloud in macOS Catalina, a red circle notification will display constantly on the icon for System Preferences.

There is a way to disable the ‘Red Badge of Notification,’ but it comes with a caveat, described below.

First, here’s how to check the setting at the command line, using Terminal (or similar console):

$ defaults read com.apple.systempreferences AttentionPrefBundleIDs

This should display 1 when the alert setting is set. To disable this alert use the following command:

$ defaults write com.apple.systempreferences AttentionPrefBundleIDs 0 && killall Dock

This changes the setting and restarts the Dock, which should remove the notification.

To reset this preference, run:

$ defaults write com.apple.systempreferences AttentionPrefBundleIDs 1

This should restore notifications on the System Preferences icon.

The Caveat

Note that this setting will hide all System Preferences alerts, so when updates are available they will not be displayed visually on the icon (because the badge has been disabled).

Therefore it is important when using this setting to check for updates manually at regular intervals (or ignore them altogether, but this isn’t recommended), which can be done by:

  1. Clicking on the Apple menu (apple icon, upper left corner) and selecting ‘System Preferences’ (or even About This Mac|Software Update, though that’s a longer path), or
  2. Opening System Preferences and seeing if a notification is displayed on its icon, and/or clicking through to the preference itself to see if updates are available