daniel@goldmember:~$ openssl s_client -connect masto.rootdc.xyz:443 | openssl x509 -noout -dates
depth=2 O = Digital Signature Trust Co., CN = DST Root CA X3
verify return:1
depth=1 C = US, O = Let's Encrypt, CN = Let's Encrypt Authority X3
verify return:1
depth=0 CN = masto.rootdc.xyz
verify error:num=10:certificate has expired
notAfter=Nov 17 19:35:43 2019 GMT
verify return:1
depth=0 CN = masto.rootdc.xyz
notAfter=Nov 17 19:35:43 2019 GMT
verify return:1
notBefore=Aug 19 19:35:43 2019 GMT
notAfter=Nov 17 19:35:43 2019 GMT
DONE