fix replace regexp

static/js/graph.js

@@ -12,7 +12,7 @@ $(function() {
             property = new_property;
             
             if (history.pushState) {
-                var newurl = window.location.href.replace(/property=./,'property='+new_property);
+                var newurl = window.location.href.replace(/property=[a-z]+/,'property='+new_property);
                 window.history.pushState({path:newurl},'',newurl);
             }
         }