Sign domain certificate like an intermediate certificate authorities

Feature Requests
1

Hello,

Can I use letsencrypt client to sign my domain certificate like an intermediate certificate authority?
(to sign www.mydomain.com using r3 certificate.)

ISRG Root X1 > R3 > community.letsencrypt.org

2

No.
Only server authentication and client authentication "roles" are supported.

3

Let's Encrypt does not offer subsidiary CAs from their chain of trust.

Also, the intermediate certificates used have the pathlen set to 0:

            X509v3 Basic Constraints: critical
                CA:TRUE, pathlen:0

(Source: Chain of Trust - Let's Encrypt)

That means that any certificate signed by R3 or E1 can never be a certificate with "CA:TRUE", so any cert issued by R3 or E1 can not be used to sign other certificates.