Let's encrypt gets disabled if user has no permission to set/change it
How to reproduce it in version 3.1.2:
- as admin: activate let's encrypt ssl & ssl for a subdomain (vhost)
- as user WITHOUT let's encrypt privileges/limit: just VIEW the vhost and click trough the tabs
- immediately the interface shows one change pending in the notification bar, and a view into the ispconfig database shows that the "ssl_lets_encrypt" is set to no
This means that If an admin activates let's encrypt for a vhost, and a normal user checks afterwards the settings of the vhost, he will disable the let's encrypt and make the httpS unusable (or even the whole website as probably in most cases the httpS redirection is activated). I "fixed" the issue by giving all the users the ssl and let's encrypt permission.