diff -r 769fefae7c81 -r 449c9539887a runtime/NevowServer.py
--- a/runtime/NevowServer.py	Wed Dec 18 13:31:22 2019 +0100
+++ b/runtime/NevowServer.py	Thu May 28 11:16:59 2020 +0100
@@ -179,7 +179,13 @@
 
         setattr(self, 'action_' + name, callback)
 
-        self.bindingsNames.append(name)
+        if name not in self.bindingsNames:
+            self.bindingsNames.append(name)
+
+
+    def delSettings(self, name):
+        if name in self.bindingsNames:
+            self.bindingsNames.remove(name)
 
 
 ConfigurableSettings = ConfigurableBindings()