No, there's a misunderstanding. You can extract the message the user entered/received BEFORE/AFTER the en-/decryption. eg. a keylogger, a screencapture, extrac

No, there's a misunderstanding. You can extract the message the user entered/received BEFORE/AFTER the en-/decryption. eg. a keylogger, a screencapture, extracting memory from the processes, just recording the screen from behind the user, ...