Check if cert is for real

Hi Community,

I’ve got mails for a testing cert II issued once up on a time. How to be absolutely sure that we use a real one. So that I can Unsubscribe from the buggy test cert list?

Thank you!

If it was issued by “Let’s Encrypt Authority X1” then it’s a real trusted cert, if it was issued by “happy hacker fake CA” then it’s a test cert.