Huh? It's a web app. If you set up https, no data is ever sent to the server unencrypted.

Likewise setting up FDE means your data is encrypted on the server.

> but this doesn't guarantee that your data will be safe

I don't get what you're trying to get at here. If you're taking about bugs compromising the encryption then I guess this applies to practically every software out there making this a moot discussion.