Minor typo fix

web/SystemAO/advance/switchAccount.html

@@ -170,7 +170,7 @@
                             showError(data.error);
                         }else{
                             //Reset the browser pool id
-                            browserAccountPoolUUID = "";
+                            browserAccountPoolUUID = undefined;
                             localStorage.removeItem("ao_acc");
                             hideError();
                             listAllStoredAccounts();