The root CA certificate for Letsencrypt expires today. They have changed to a new provider, but some older systems or libraries do not support it. I am able to browse to my Joplin server that is signed with a Letsencrypt cert, but Joplin reports certificate expired. For reference: https://letsencry…

Letsencrypt root CA certificate expiration

tessus Closed 1 October 2021 00:36 17

use this one instead:

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