Let's Encrypt wildcard certificates and ACMEv2 are available today! More information can be found here: https://t.co/0SdH98Oabn
— Let's Encrypt (@letsencrypt) March 13, 2018
參考「ACME v2 and Wildcard Certificate Support is Live」這邊的說明，裡面有提到 Wildcard Certificate 需要有 ACMEv2 的 client：
Wildcard certificates are only available via ACMEv2. In order to use ACMEv2 for wildcard or non-wildcard certificates you’ll need a client that has been updated to support ACMEv2. It is our intent to transition all clients and subscribers to ACMEv2, though we have not set an end-of-life date for our ACMEv1 API yet.
然後我之後打算把 letsencrypt.tw 的資料改丟到我的 Wiki 上，這樣改起來比較簡單...