this is a package management error that occurs when you do not have a certificate file, and cause Package Control not to update itself to fix this error.
A quick fix is ββto have a dummy certificate file using the security command:
sudo security add-trusted-cert -d -r trustRoot -k /Library/Keychains/System.keychain ~/Downloads/localhost.cert
You can create a dummy certificate this tool
Then restart sublime and force update Package Management manually with β ^ P
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