cwp several domains using one single email server lets encrypt certificate

I recommend all the email users from many diferrent domains that i host im my CWP Server, to use Thunderbird as email client, once my postfix server uses the Lets Encrypyt certificate created to my domain, and "Thunderbird add account feature" when configuring finds the imap.mycustomerdomain.com as also smtp.imap.mycustomerdomain.com, but always complains that the certificate does not match the same domain.

Someone knows how to solve it in a such way that the add accounts works fine with no any manual action in Thunderbird, Gmail android etc?

Since 2018 i always change the imap & smtp server hostname to myhost.mydomain.com rather then use the automatically found imap.mycustomerdomain.com, once the certificate always causes warnings of security certificate exception or other times that do not works indeed.

Thanks in advance!