diff --git a/examples/ignore_websocket.py b/examples/ignore_websocket.py
index 48093951e..f7a94bdf3 100644
--- a/examples/ignore_websocket.py
+++ b/examples/ignore_websocket.py
@@ -26,7 +26,8 @@ def done(context):
 
 @concurrent
 def response(context, flow):
-    if flow.response.headers.get_first("Connection", None) == "Upgrade":
+    value = flow.response.headers.get_first("Connection", None)
+    if value and value.upper() == "UPGRADE":
         # We need to send the response manually now...
         flow.client_conn.send(flow.response.assemble())
         # ...and then delegate to tcp passthrough.