Wherever a key pair is shown (the guide's last step, the key dialog) a
"Save credentials" button writes it to a .pithoskey file, and Users &
keys gains "Open saved credentials" to read one back.
- With a password (any host): PBKDF2-SHA256, 600k iterations, AES-256-GCM,
done in the page with WebCrypto.
- With the Theseus vault (default in Theseus): AES-256-GCM under a key the
add-on derives from the vault (pithos/credentials/v1, now fixed), so
there is no extra password; a locked vault raises the PIN prompt first.
The add-on saves through a native dialog, since the sidebar page has no
download path.
Only the user name and date stay readable, to tell files apart.
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