app: fixed undefined logic object breaking generator

js/erp5_loader.js

@@ -2683,7 +2683,7 @@
     if (element.type === "a") {
       icon = (element.attributes || {})["data-icon"] || default_icon;
       // because of custom a in service_instance_status!
-      if (!element.logic.plain_link) {
+      if (!(element.logic || {}).plain_link) {
         string += " ui-btn ui-shadow ";
       }
       if (icon) {