Happy New Year.
Hmm, Charlie Stross's blog [¹] got a new Let's Encrypt certificate this morning. Works fine in Firefox, not so much in Liferea/wget/curl. I'm guessing it's a matter of which certificate store is used. On up-to-date Ubuntu 20.04.1. Could be something trivial or it could be the first sign of a minor panic.
Let's Encrypt are rolling out new certificates but this is signed by their R3 certificate which has been in use for a few months, AIUI.
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