Symmetric encryption in Nautilus

@Accessoires>Files

Could you add a context menu item “Encrypt Symmetric”, i would like to encrypt files using a passphrase, just as an extra layer of protection when the system is booted. This can already be done via the terminal (https://www.gnupg.org/gph/en/manual/x110.html). But a context menu item would be very handy.

Decryption already works as “files” recognizes the file regardless of its encryption type.

Related issues

• Is duplicate of #6607 (closed)

Original created by @macmc on 10361 (Redmine)