Index: Paramifiers.js
===================================================================
--- Paramifiers.js	(revision 4165)
+++ Paramifiers.js	(working copy)
@@ -34,7 +34,8 @@
 
 config.paramifiers.open = {
 	onstart: function(v) {
-		story.displayTiddler("bottom",v,null,false,null);
+		if(!readOnly || store.tiddlerExists(v) || store.isShadowTiddler(v))
+			story.displayTiddler("bottom",v,null,false,null);
 	}
 };