@psykid, this advice from @petercooperjr is very important because there is disagreement between different verifiers about whether the Let's Encrypt long chain should be considered valid. While Let's Encrypt believes it is justifiable, and many clients happily accept it, there are some that don't, and they can also present an argument for their behavior. The option that @petercooperjr mentions changes this behavior in the TLS library that your code is calling locally. (If you're using a different TLS client library than OpenSSL, there might be a different option whose behavior corresponds to this one.)
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