It can be anything! An apex, subdomain, or even a URL.

Results formail.funfun.app

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2024-04-04T03:36:40.9	2024-04-04T00:00:00	2024-07-03T23:59:59	funfun.app	mail.funfun.app	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2024-04-04T03:36:40.135	2024-04-04T00:00:00	2024-07-03T23:59:59	funfun.app	mail.funfun.app	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2024-01-19T04:57:42.303	2024-01-19T00:00:00	2024-04-18T23:59:59	funfun.app	mail.funfun.app	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2024-01-19T04:57:40.784	2024-01-19T00:00:00	2024-04-18T23:59:59	funfun.app	mail.funfun.app	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2023-11-04T18:52:10.712	2023-11-04T00:00:00	2024-02-02T23:59:59	funfun.app	mail.funfun.app	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2023-11-04T18:52:10.304	2023-11-04T00:00:00	2024-02-02T23:59:59	funfun.app	mail.funfun.app	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"