1 files changed, 2 insertions, 2 deletions
diff --git a/synapse/config/server.py b/synapse/config/server.py
index 0ec1b0fadd..7525765fee 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -1066,12 +1066,12 @@ KNOWN_RESOURCES = (
 
 
 def _check_resource_config(listeners):
-    resource_names = set(
+    resource_names = {
         res_name
         for listener in listeners
         for res in listener.get("resources", [])
         for res_name in res.get("names", [])
-    )
+    }
 
     for resource in resource_names:
         if resource not in KNOWN_RESOURCES: