So, my understanding you had upgrade your System from 15 to 16 ? and issue is not fixed?
I think you can easy to check internal and external SSL LE Certificate.
from internal checks : openssl s_client -showcerts -connect FQDN.address.com:Port
But Cert Manager says it’s not
SSL Checker gives me:
No SSL certificates were found on FQDN. Make sure that the name resolves to the correct server and that the SSL port (default is 443) is open on your server’s firewall.
Successfully updated certificate named "*fqdn.whatitis.com*"
Certificate named "*fqdn.whatitis.com-fullchain*" is going to expire in less than a month. Please update this certificate in Certificate Manager
But at least SSL access is working again and the Ajax error is gone
You SO are right about that. I will note that I’ve had good luck doing bug reports and waiting on a response from the devs, but it’s still in no way ideal to have an update break the system.