Let's Encrypt certificate unexpectedly got expired on 4th March 2020: Let's Encrypt 2020.02.29 CAA Bug

Symptoms

• Let's Encrypt certificate unexpectedly got expired on March 4th, 2020

• Certificate marked is invalid

• The website shows a warning message saying the HTTPS connection is not secured

• A notification from Let's Encrypt has been received:

  CONFIG_TEXT: ACTION REQUIRED: Renew these Let's Encrypt certificates by March 4
  We recently discovered a bug in the Let's Encrypt certificate authority code,
  described here:
  https://community.letsencrypt.org/t/2020-02-29-caa-rechecking-bug/114591
  Unfortunately, this means we need to revoke the certificates that were affected
  by this bug, which includes one or more of your certificates. To avoid
  disruption, you'll need to renew and replace your affected certificate(s) by
  Wednesday, March 4, 2020. We sincerely apologize for the issue.
  ...
  Your affected certificate(s), listed by serial number and domain names:
  0123456789abcdef0123456789abcdef0123: webmail.example.com www.example.com example.com alias.example.com

Cause

Due to the Let's Encrypt 2020.02.29 CAA Rechecking Bug, some Let's Encrypt certificates were revoked on 4th March 2020.

Resolution

Update or install to the latest SSL It! extension version 1.2.2-653

Workaround

If update is not possible for some reason you may try the following workaround:

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