On 30th September 2021, the root certificate that Let's Encrypt are currently using, the IdentTrust DST Root CA X3 certificate, will expire. You may or may not need to do anything about this Root CA expiring, but I'm betting a few things will probably break on that day so here's what you need to know! There's a long backstory This seems like a shameless plug, but if you really want to know more about how Certificate Authorities (CA) and Certificate Chains work, you should consider joining me on the Pra...