mac os lion root zertifikat erneuern:

https://mjtsai.com/blog/2021/09/24/some-web-sites-will-stop-working-with-el-capitan-and-older/#comment-3538503

1. Download this Root Certificate:
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NAME:
"ISRG Root X1"
(✅ Self-signed, ❌ NOT Cross-signed)

URL:
https://letsencrypt.org/certs/isrgrootx1.der

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2. Verify that the fingerprints match:
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So you know that the Root Certificate I've linked to is in fact the one that LE provides and Apple has certified/trusted.

This is for *your* safety since you *shouldn't* trust me.

FINGERPRINT (SHA-1):
CABD2A79A1076A31F21D253635CB039D4329A5E8

SOURCE:
https://letsencrypt.org/certificates/ (Active > ISRG Root X1 > Self-signed > der)
https://crt.sh/?id=9314791

WHAT APPLE SHIPS 10.12.1+:
https://support.apple.com/en-us/HT207189
- Search for: "ISRG Root X1"

You should see that the fingerprints match between and .

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4. Install the certificate:
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- Via "Keychain Access.app"
- `File > Import Items...`

You can install it into either the `login` or `system` keychain. But not `System Roots` (which is where it *would* be, if we were on 10.12.1+)

- login = Current user only
- system = All users

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5. Manually "Trust" that certificate:
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- Find it ("ISRG Root X1") in the list and double click on it.
- Open the "▶ Trust" area.
- Set: `When using this certificate:` to `Always Trust`
- Close the window, which will ask you to verify with your login password.

🏁 Done!