What is needing is FOSS that you can use a separate program for encryption and for communication (which do not necessarily need to run on the same computer; the

What is needing is FOSS that you can use a separate program for encryption and for communication (which do not necessarily need to run on the same computer; the service need not care about that, nor how they are sandboxed (on the same computer) or connected (on different computers), nor what ciphers are in use, what language or character set it is written in, picture formats, etc).