diff --git a/app/matrix/lib/synapse/homeserver-ng.yaml b/app/matrix/lib/synapse/homeserver-ng.yaml
index 7d0a98a..3e11a1e 100644
--- a/app/matrix/lib/synapse/homeserver-ng.yaml
+++ b/app/matrix/lib/synapse/homeserver-ng.yaml
@@ -130,3 +130,8 @@
 # Allow federated public rooms browsing
 allow_public_rooms_without_auth: true
 allow_public_rooms_over_federation: true
+
+## Experimental Features ##
+experimental_features:
+  # Message threading support
+  msc3440_enabled: true