feat: add keyoxide to last slide

openpgp-workshop/index.md

@@ -105,19 +105,6 @@ What are some useful ways we can use OpenPGP:
 
 ---
 
-## What's Happening Behind the Scenes
-
-* GPG generates a symmetric key (AES) and uses that to encrypt the bulk of the data
-
-* RSA/ECC is used only to encrypt the symmetric key
-
-* The encrypted data packet contains metadata about which public keys were encrypted to
-    * This can be hidden using `--hidden-recipient/-R`
-
-* Inspect packets using `gpg --list-packets <file.asc/file.gpg>`
-
----
-
 ## Verifying Signatures 📝
 
 * Go to: https://www.qubes-os.org/downloads/
@@ -230,6 +217,8 @@ What are some useful ways we can use OpenPGP:
 
 ## Further Studies
 
+* [keyoxide](https://keyoxide.org/): decentralized tool to create and verify decentralized online identities
+
 * [pass](https://www.passwordstore.org/): Unix based `gpg` password manager
 
 * [OpenPGP for application developers](https://openpgp.dev/book/): Deep dive on OpenPGP