The error occurs when the contact key is missing or empty in the Let's Encrypt API response, causing null to be passed to Account::__construct (), which expects an array.

Actual behavior When running using an unauthenticated proxy, synctool.php writes errors to log for undefined array keys.

$ _POST or $ _GET are two special PHP functions that are used to get variables from a user-filled form. While using these functions, a user may encounter an error, stating that there is an undefined ...