diff --git a/topics/filtering.md b/topics/filtering.md
index e69de29..65169d7 100644
--- a/topics/filtering.md
+++ b/topics/filtering.md
@@ -0,0 +1,5 @@
+# Filtering
+
+In decentralized networks, whether federated or p2p, there is often no global search functionality.
+
+This issue being discussed in Mastodon: https://github.com/tootsuite/mastodon/issues/9529
diff --git a/topics/security.md b/topics/security.md
index dfbd95e..614168f 100644
--- a/topics/security.md
+++ b/topics/security.md
@@ -7,3 +7,5 @@ Addresses key establishment, authentication, and confidentiality service
 [Inside MLS, the New Protocol for Secure Enterprise Messaging](https://www.darkreading.com/perimeter/inside-mls-the-new-protocol-for-secure-enterprise-messaging/d/d-id/1335075)
 
 [messaginglayersecurity.rocks](https://messaginglayersecurity.rocks/)
+
+Object capability security authorization system